ML25126A252
| ML25126A252 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 06/10/2025 |
| From: | Mark Yoo NRC/NRR/DNRL/NLRP |
| To: | Wilson C Constellation Energy Company |
| References | |
| EPID L-2024-SLR-0000 | |
| Download: ML25126A252 (1) | |
Text
Christopher D. Wilson Director, License Renewal Constellation Energy Generation, LLC 200 Energy Way, KSA-3E Kennet Square, PA 19348
SUBJECT:
DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 - REPORT FOR THE AGING MANAGEMENT AUDIT REGARDING THE SUBSEQUENT LICENSE RENEWAL APPLICATION REVIEW (EPID NO. L-2024-SLR-0000)
Dear Christopher D. Wilson:
By letter dated April 17, 2024 (Agencywide Documents Access and Management System (ADAMS) Package Accession No. ML24108A007), as supplemented by letters dated February 20, 2025 (ML25051A253), March 13, 2025 (ML25072A153), and April 28, 2025 (ML25118A278), Constellation Energy Generation, LLC (CEG) submitted an application for subsequent license renewal (SLR) of Renewed Facility Operating License Nos. DPR-19 and DPR-25 for Dresden Nuclear Power Station (Dresden), Units 2 and 3, to the U.S. Nuclear Regulatory Commission (NRC, staff). Constellation submitted the application pursuant to Title 10 of the Code of Federal Regulations Part 54, Requirements for Renewal of Operating Licenses for Nuclear Power Plants, for SLR.
The NRC staff completed its aging management audit from June 17, 2024 - March 14, 2025, in accordance with the audit plan (ML24138A181). The audit report is enclosed. If you have any questions, please contact me by email at Mark.Yoo@nrc.gov.
Sincerely, Mark Yoo, Senior Project Manager License Renewal Projects Branch Division of New and Renewed Licenses Office of Nuclear Reactor Regulation Docket Nos: 50-237 and 50-249
Enclosure:
Audit Report June 10, 2025 Signed by Yoo, Mark on 06/10/25
C. Wilson 2
SUBJECT:
DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 - REPORT FOR THE AGING MANAGEMENT AUDIT REGARDING THE SUBSEQUENT LICENSE RENEWAL APPLICATION REVIEW (EPID NO. L-2024-SLR-0000)
DATED: JUNE 10, 2025 DISTRIBUTION:
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Christopher.Wilson2@constellation.com Iba.Ello@constellation.com Allison.Stalker@constellation.com ADAMS Accession Nos RPT: ML25126A252 NRR-106 OFFICE PM:NRLP:DNRL BC:NCSG:DNRL BC:SNSB:DSS BC:ELTB:DEX NAME MYoo SBloom DMurdock PKoch DATE 05/7/2025 03/10/2025 03/13/2025 03/17/2025 OFFICE BC:NPHP:DNRL BC:NVIB:DNRL BC:ESEB:DEX LA:NRLP:DNRL NAME MMitchell ABuford ITseng KBratcher DATE 03/21/2025 05/12/2025 05/10/2025 05/12/2025 OFFICE BC:NRLP:DNRL PM:NRLP:DNRL NAME ANeuhausen MYoo DATE 06/092025 6/10/25
Enclosure Aging Management Audit Report Dresden Nuclear Power Station, Units 2 and 3 Subsequent License Renewal Application June 17, 2024 - March 14, 2025 Division of New and Renewed Licenses Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission
ii U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR REACTOR REGULATION DIVISION OF NEW AND RENEWED LICENSES Docket No:
50-237 and 50-249 License No:
Constellation Energy Generation, LLC (CEG)
Facility:
Dresden Nuclear Power Station (Dresden or DNPS), Units 2 and 3 Location:
Rockville, Maryland Morris, Illinois Dates:
June 17, 2024 - March 14, 2025 Approved By:
Steven D. Bloom, Chief Corrosion and Steam Generator Branch Division of New and Renewed Licenses Angie R. Buford, Chief Vessels and Internals Branch Division of New and Renewed Licenses Ian Tseng, Chief Structural, Civil, Geotech Engineering Branch Division of Engineering and External Hazards Alissa Neuhausen, Acting Chief License Renewal Projects Branch Division of New and Renewed Licenses Patrick Koch, Acting Chief Long Term Operations and Modernization Branch Division of Engineering and External Hazards Darrell Murdock, Chief Nuclear Systems Performance Branch Division of Safety Systems Matthew A. Mitchell, Chief Piping and Head Penetrations Branch Division of New and Renewed Licenses
iii NRC Staff Reviewers:
Name Organization Naeem Iqbal PRA Licensing B/Division of Risk Assessment Adakou Foli Long Term Operations & Modernization (ELTB)/Division of Engineering and External Hazards (DEX)
Jorge Cintron-Rivera ELTB/DEX Kenn Miller ELTB/DEX Liliana Ramadan ELTB/DEX Matt McConnell ELTB/DEX Ata Istar Structural, Civil, Geotech Engineering (ESEB)/DEX George Thomas ESEB/DEX George Wang ESEB/DEX Shaohua Lai ESEB/DEX Si Hwan Park ESEB/DEX John Wise Division of New and Renewed Licenses (DNRL)
Andrew Johnson Corrosion and Steam Generator (NCSG)/DNRL Brian Allik NCSG/DNRL Devendra Ray NCSG/DNRL Gregory Makar NCSG/DNRL Joel Jenkins NCSG/DNRL Leslie Terry NCSG/DNRL Lydiana Alvarado NCSG/DNRL Matthew Yoder NCSG/DNRL Miranda Ross NCSG/DNRL Paul Klein NCSG/DNRL Reena Boruk NCSG/DNRL William (Tony) Gardner NCSG/DNRL Ali Rezai Piping and Head Penetrations (NPHP)/DNRL Bart Fu NPHP/DNRL Karen Sida NPHP/DNRL Seung Min NPHP/DNRL Varoujan Kalikian NPHP/DNRL Cory Parker Vessels and Internals (NVIB)/DNRL David Dijamco NVIB/DNRL Emma Haywood NVIB/DNRL Eric Palmer NVIB/DNRL James Medoff NVIB/DNRL Michael Benson NVIB/DNRL On Yee NVIB/DNRL Steven Levitus NVIB/DNRL
iv Name Organization Derek Scully Containment and Plant Systems (SCPB)/Division of Safety Systems (DSS)
Hanry Wagage SCPB/DSS Raul Hernandez SCPB/DSS Rob Atienza SCPB/DSS Jo Ambrosini Nuclear Systems Performance/DSS Brandon Wise Nuclear Methods and Fuels/DSS Mark Yoo License Renewal Projects (NLRP)/DNRL Chris Tyree NLRP/DNRL Bill Rogers NLRP/DNRL
v TABLE OF CONTENTS TABLE OF CONTENTS................................................................................................................v ACRONYMS AND ABBREVIATIONS.........................................................................................viii 1.
Introduction..............................................................................................................................1 2.
Audit Activities.........................................................................................................................2 SLRA AMP B.2.1.1, ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD 3
SLRA AMP B.2.1.2, Water Chemistry 3
SLRA AMP B.2.1.3, Reactor Head Closure Stud Bolting Program 5
SLRA AMP B.2.1.4, BWR Vessel ID Attachment Welds 6
SLRA AMP B.2.1.5, BWR Stress Corrosion Cracking 7
SLRA AMP B.2.1.6, BWR Penetrations 8
SLRA AMP B.2.1.7, BWR Vessel Internals 9
SLRA AMP B.2.1.8, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) 11 SLRA AMP B.2.1.9, Flow-Accelerated Corrosion 12 SLRA AMP B.2.1.10, Bolting Integrity 13 SLRA AMP B.2.1.11, Open Cycle Cooling Water System 15 SLRA AMP B.2.1.12, Closed Treated Water Systems 16 SLRA AMP B.2.1.13, Inspection of Overhead Heavy Load and Light Load (Related to Refueling) Handling Systems 17 SLRA AMP B.2.1.14, Compressed Air Monitoring 19 SLRA AMP B.2.1.15, Fire Protection 19 SLRA AMP B.2.1.16, Fire Water System 21 SLRA AMP B.2.1.17, Outdoor and Large Atmospheric Metallic Storage Tanks 23 SLRA AMP B.2.1.18, Fuel Oil Chemistry 24 SLRA AMP B.2.1.19, Reactor Vessel Material Surveillance 25 SLRA AMP B.2.1.20, One-Time Inspection 26 SLRA AMP B.2.1.21, Selective Leaching 27 SLRA AMP B.2.1.22, ASME Code Class 1 Small-Bore Piping Program 27 SLRA AMP B.2.1.23, External Surfaces Monitoring of Mechanical Components 28 SLRA AMP B.2.1.24, Inspection of Internal Surfaces in Miscellaneous Piping and Ducting Components 29 SLRA AMP B.2.1.25, Lubricating Oil Analysis 30 SLRA AMP B.2.1.26, Monitoring of Neutron-Absorbing Materials Other Than Boraflex 31 SLRA AMP B.2.1.27, Buried and Underground Piping and Tanks 32
vi SLRA AMP B.2.1.28, Internal Coatings/Linings for In-Scope Piping, Piping Components, Heat Exchanger, and Tanks 33 SLRA AMP B.2.1.29, ASME Section XI, Subsection IWE 35 SLRA AMP B.2.1.30, ASME Section XI, Subsection IWF 39 SLRA AMP B.2.1.31, 10 CFR Part 50, Appendix J 42 SLRA AMP B.2.1.32, Masonry Walls 42 SLRA AMP B.2.1.33, Structures Monitoring 43 SLRA AMP B.2.1.34, Inspection of Water-Control Structures Associated with Nuclear Power Plants 46 SLRA AMP B.2.1.35, Protective Coating Monitoring and Maintenance 48 SLRA AMP B.2.1.36, Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements 49 SLRA AMP B.2.1.37, Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Used in Instrumentation Circuits 51 SLRA AMP B.2.1.38, Electrical Insulation for Inaccessible Medium-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements 52 SLRA AMP B.2.1.39, Electrical Insulation for Inaccessible Instrument and Control Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements 54 SLRA AMP B.2.1.40, Electrical Insulation for Inaccessible Low-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements 56 SLRA AMP B.2.1.41, Metal Enclosed Bus 58 SLRA AMP B.2.1.42, Electrical Cable Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements 59 SLRA AMP B.3.1.1, Fatigue Monitoring 60 SLRA AMP B.3.1.2, Neutron Fluence Monitoring 61 SLRA AMP B.3.1.3, Environmental Qualification of Electric Equipment 62 SLRA TLAA Section 4.1, Identification of Time-Limited Aging Analyses (TLAAs) 63 SLRA TLAA Section 4.2.1, Reactor Pressure Vessel and Internals Neutron Fluence Analyses 65 SLRA TLAA Section 4.2.2, Reactor Pressure Vessel Upper-Shelf Energy (USE)
Analyses 66 SLRA TLAA Section 4.2.3, Reactor Pressure Vessel Adjusted Reference Temperatures (ART) Analyses 67 SLRA TLAA Section 4.2.4, Reactor Pressure Vessel Pressure-Temperature (p-T)
Limits 68 SLRA TLAA Section 4.2.5, Reactor Pressure Vessel Circumferential Weld Failure Probability Analyses, and SLRA Section 4.2.6, Reactor Pressure Vessel Axial Weld Failure Probability Analyses 69 SLRA TLAA Section 4.2.7, Reactor Pressure Vessel Reflood Thermal Shock Analysis 70
vii SLRA TLAA Section 4.2.8, Core Shroud Reflood Thermal Shock Analysis 70 SLRA TLAA Section 4.2.9, Jet Pump Beam Bolt and Access Hole Cover Bolt Preload Relaxation Analyses 71 SLRA TLAA Section 4.2.10, Jet Pump Auxiliary Wedge Assembly Loss of Preload Analysis 72 SLRA TLAA Section 4.2.11, Unit 2 Jet Pump Riser Repair/Mitigation Clamps Loss of Preload Analysis 73 SLRA TLAA Section 4.2.12, Unit 2 and 3 Core Spray Replacement Piping Bolting Loss of Preload Evaluation 74 SLRA TLAA Section 4.2.13, Core Shroud Repair Stabilizer Assembly Bracket Preload Relaxation Analysis 75 SLRA TLAA Section 4.3.1, Transient and Cumulative Usage Projections for 80 Years76 SLRA TLAA Section 4.3.2, ASME Section III, Class 1 Fatigue Analyses 77 SLRA TLAA Section 4.3.3, Environmental Fatigue Analyses For RPV and Class 1 Piping 78 SLRA TLAA Section 4.3.4, ASME Section III, Class 1 Fatigue Waivers 80 SLRA TLAA Section 4.3.5, ASME Section III, Class 2 & 3, and ANSI B31.1 Allowable Stress Analyses and Associated HELB Analyses 81 SLRA TLAA Section 4.3.6, Reactor Pressure Vessel Internals Fatigue Analyses 82 SLRA TLAA Section 4.3.7, Fatigue Analysis of the Isolation Condensers 84 SLRA TLAA Section 4.4, Environmental Qualification of Electric Equipment 85 SLRA TLAA Section 4.7.1, Reactor Building Overhead Crane Load Cycles 86 SLRA TLAA Section 4.7.2, Crack Growth Calculation of a Postulated Flaw in the Heat Affect Zone of an Arc Strike in the Torus Shell 87 SLRA TLAA Section 4.7.3, Radiation Degradation of Drywell Shell Expansion Gap Polyurethane Foam 88 SLRA TLAA Section 4.7.4, Generic Letter 81-11 Crack Growth Analysis To Demonstrate Conformance To The Intent Of NUREG-0619, BWR Feedwater Nozzle And Control Rod Drive Return Line Nozzle Cracking 89 SLRA TLAA Section 4.7.5, Unit 2 Core Spray Replacement Piping Fatigue and Leakage Assessment 90 SLRA TLAA Section 4.7.6, Unit 2 Reactor Pressure Vessel Closure Flange Flaw 91 SLRA TLAA Section 4.7.7, Isolation Condenser Weld Flaw 92 SLRA TLAA Section 4.7.8, Protective Coatings 93 AMR Items Not Associated with an AMP 94 3.
Supplements to the SLRA...................................................................................................102 4.
Audit Questions Provided to CEG.......................................................................................102 5.
Applicant Personnel Contacted During Audit......................................................................104 6.
Exit Meeting.........................................................................................................................104
viii ACRONYMS AND ABBREVIATIONS ADAMS Agencywide Documents Access and Management System ALE Adverse localized environments AMP Aging Management Program AMR Aging management review AR Action report ART Adjusted Reference Temperatures ASME American Society for Mechanical Engineers BWR Boiling Water Reactor BWRVIP Boiling Water Reactor Vessel Internals Program CAP Corrective Action Program CASS Cast austenitic stainless steel CEG Constellation Energy Generation, LLC CLB Current licensing basis CRD Control rod drive CRDG Control rod drive guide CUF Cumulative usage factor DBE Design Basis Event DNPS Dresden Nuclear Power Station EAF Environmentally assisted fatigue ECCS Emergency Core Cooling System EDG Emergency diesel generator EPC Erosion in piping and components EPRI Electric Power Research Institute EQ Environmental Qualification FAC Flow-accelerated corrosion FE Further evaluation FW Feedwater HELB High-energy line break HPCI High-pressure coolant injection ISI In-Service Inspection ISP Integrated Surveillance Program I&C Instrumentation and control I&E Inspection and evaluation JPRB Jet pump riser brace LP Low Pressure LPCI Low Pressure Coolant Injection LR License renewal MS Main steam
ix MSIV Main steam isolation valve NRC Nuclear Regulatory Commission OE Operating experience PBD Program basis document RAI Request for Additional Information RBEDT Reactor Building Equipment Drain Tank RCI Request for Confirmation of Information RCS Reactor coolant system RPV Reactor pressure vessel RR Relief request RVI Reactor vessel internal SBO Station blackout SCC Stress corrosion cracking SIA Structural Integrity Associates SLR Subsequent license renewal SLRA Subsequent license renewal application SSC Systems, structures, and components TLAA Time-Limited Aging Analyses UFSAR Updated final safety analysis report USE Upper-Shelf Energy UT Ultrasonic testing
1 Report for the Aging Management Audit Dresden Nuclear Power Station, Units 2 and 3 Subsequent License Renewal Application 1.
Introduction The U.S. Nuclear Regulatory Commission (NRC) staff conducted an aging management audit of Constellation Energy Generation, LLC (CEG, the applicant) of (1) plant-specific operating experience (OE), (2) the methodology used to identify the systems, structures, and components (SSCs) to be included within the scope of license renewal (LR) and subject to an aging management review (AMR) (Scoping and Screening Portion), and (3) aging management programs (AMPs), AMR items, Time-Limited Aging Analyses (TLAAs), and associated bases and documentation as applicable (AMP and TLAA Portion) for the subsequent license renewal (SLR) of Renewed Facility Operating License Nos. DPR-19 and DPR-25 for Dresden Nuclear Power Station (Dresden), Units 2 and 3, respectively.
The purpose of the plant-specific OE portion of the audit is to identify examples of age-related degradation, as documented in the applicants corrective action program (CAP) database, and to provide a basis for the staffs conclusions on the ability of the applicants proposed AMPs to manage the effects of aging in the period of extended operation. CEG searched their OE database and provided the results for the associated AMPs and TLAAs for NRC staff review.
Additional word searches were performed by CEG upon the NRC staffs request, and the results were provided to the NRC staff for review.
The purpose of the Scoping and Screening portion of the audit is to evaluate the scoping and screening process as documented in the SLR application, implementing procedures, reports, and drawings, such that the NRC staff:
Obtain an understanding of the process used to identify the SSCs within the scope of LR and to identify the structures and components subject to an Aging Management Review (AMR); and Have sufficient docketed information to allow the staff to reach a conclusion on the adequacy of the scoping and screening methodology as documented and applied.
The purpose of the AMP and TLAA Portion of the audit is to:
Examine CEGs AMPs, AMR items, and TLAAs for Dresden, Units 2 and 3; Verify CEGs claims of consistency with the corresponding NUREG-2191, Generic Aging Lessons Learned for Subsequent License Renewal (GALL-SLR) Report, issued in July 2017, AMPs, and AMR items; and Assess the adequacy of the TLAAs.
Enhancements and exceptions will be evaluated on a case-by-case basis. The NRC staffs review of enhancements and exceptions will be documented in the safety evaluation (SE). The regulatory basis for the audit was Title 10 of the Code of Federal Regulations (10 CFR) part 54, Requirements for Renewal of Operating Licenses for Nuclear Power Plants. The staff also considered the guidance contained in NUREG-2192, Standard Review Plan for Review of
2 Subsequent License Renewal Applications for Nuclear Power Plants (SRP-SLR), dated July 2017, and NUREG-2191. The SRP-SLR allows an applicant to reference in its SLR application the AMPs described in the GALL-SLR Report. By referencing the GALL-SLR Report AMPs, the applicant concludes that its AMPs correspond to those AMPs reviewed and approved in the GALL-SLR Report and that no further staff review is required. If an applicant credits an AMP for being consistent with a GALL-SLR Report program, it is incumbent on the applicant to ensure that the plant program contains all of the elements of the referenced GALL-SLR Report program. The applicant should document this determination in an auditable form and maintain the documentation onsite.
2.
Audit Activities A regulatory audit is a planned license-related activity that includes the examination and evaluation of primarily non-docketed information. A regulatory audit is conducted to gain greater understanding of an application, to verify information, and, if applicable, to identify information that will require docketing to support the staffs conclusions that form the basis of the licensing or regulatory decision.
The subsequent license renewal application (SLRA) states that every AMP in the SLRA is consistent with the program elements of the GALL-SLR Report. To verify this claim of consistency, the staff audited each AMP, including any enhancements or exceptions associated with an AMP.
The SLRA discusses each TLAA, the disposition of the TLAA in accordance with 10 CFR 54.21(c)(1), and the basis for that disposition. To verify that the applicant provided a basis to support its disposition of the TLAA, the staff audited each TLAA.
The staff also audited AMR items not associated with an AMP to determine if the information in the SLRA is consistent with the further evaluation (FE) information in the SRP-SLR.
Furthermore, the staff audited the updated final safety analysis report (UFSAR) supplement descriptions for each AMP and TLAA for consistency with the SRP-SLR. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
From December 9-12, 2024, the staff participated in an onsite audit at Dresden, Units 2 and 3 in Morris, IL to gain a general overview of current conditions of the structures compared to the provided OE. While onsite, the staff engaged with the applicant staff, conducted walkdowns, and reviewed documents provided by the applicant.
For the OE review, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
Licensing conclusions or staff findings are not made in the audit reports since licensing and regulatory decisions cannot be made solely based on an audit. Therefore, items identified but not resolved within the scope of the audit will be addressed using other NRC processes, such as requests for additional information (RAIs), requests for confirmation of information (RCIs),
and public meetings. Licensing conclusions, staff findings, staff review of enhancements and exceptions, and resolution of audit items will be documented in the staffs SE.
3 The following sections discuss the SLRA areas reviewed by the staff.
SLRA AMP B.2.1.1, ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD Summary of Information in the Application. The SLRA states that AMP B.2.1.1, ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD, is an existing program that is consistent with the program elements in GALL-SLR Report AMP XI.M1, ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD. To verify this claim of consistency, the staff audited the SLRA AMP.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant provided a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and reviewed the OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-SSBD-SSL License Renewal Systems and Structures Scoping and Screening Basis Document Revision 1 07/21/2022 DR-PBD-AMP-XI.M1 Dresden Nuclear Power Station, Subsequent License Renewal Project, ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD, Program Basis Document Revision 1 06/09/2024 WO-00415749 Perform Weld Repair to Support M-1164D-580 10/07/2003 PI-AA-126-1001-F-01 Constellation Proprietary. Fleet Inservice Inspection Focused Area Self-Assessment Revision 2 02/28/2018 ER-AA-330 Constellation Proprietary. Conduct of Inservice Inspection Activities Revision 20 06/09/2024 EC-5771 Unit 2 Core Spray Lower Sectional Line Replacement Revision 2 03/25/2010 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements in the GALL-SLR Report AMP.
The staff also audited the description of the SLRA AMP B.2.1.1, ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD, provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in SRP-SLR.
SLRA AMP B.2.1.2, Water Chemistry Summary of Information in the Application. The SLRA states that AMP B.2.1.2, Water Chemistry, is an existing program with one exception that is consistent with the program
4 elements in GALL-SLR Report AMP XI.M2, Water Chemistry, as modified by SLR-ISG-2021 02-MECHANICAL, Updated Aging Management Criteria for Mechanical Portions of Subsequent License Renewal Guidance, dated February 2021 (ADAMS Accession No. ML20181A434). To verify this claim of consistency, the staff audited the SLRA AMP. During the audit, the staff also reviewed the exception associated with this AMP. The staff will document its review of the exception to the GALL-SLR Report AMP in the SE.
Audit Activities. The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M2 Water Chemistry Revision 1 AR 101522-02 Aging Management Program (AMP) Effectiveness Review 02/23/2018 AR 04539818 Unexpected Load Drop 11/30/2022 AR 04538011 U3 CRD Cond. and Dissolve Oxygen Above Action Level 1 11/24/2022 AR 04538093 Condensate and Feedwater Dissolved Oxygen Above Action Level 11/24/2022 AR 04538676 D3R27 Action Level 1 CPD and CRD Dissolved Oxygen (DO) 11/27/2022 AR 04543046 U3R27 S/Up Dissolve Oxygen Condition Lesson Learned 12/15/2022 AR 04119139 OLNC Lessons Learned 03/26/2018 AR 04122086 4.0 Critique-U3 OLNC 04/02/2018 AR 04069800 Feedwater and Condensate Conductivity Exceeded Goal 11/01/2017 AR 04365359 Unit 3 Stator Conductivity above Goal of CY-AA-120-440 08/25/2020 AR 04505615 Trend: U3 SWC Conductivity Rising Trend 06/15/2022 GEK 45942B GEH Proprietary. Stator Winding Cooling Water System Operation and Flushing (Constant Flow)
Not identified CY-AA-120-440 Constellation Proprietary. Stator Water Cooling Chemistry Revision 11 EPRI TR 3002000420 Turbine Generator Auxiliary System Maintenance Guide Volume 4: Generator Stator Cooling Water System December 2013 The staff also verified the applicants claim that aspects of the preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding program elements inthe GALL-SLR Report AMP.
5 The staff also verified the applicants claim that aspects of the scope of program, program element not associated with the exception identified in the SLRA are consistent with the corresponding program elements inthe GALL-SLR Report AMP.
The staff also audited the description of the SLRA AMP Water Chemistry provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.3, Reactor Head Closure Stud Bolting Program Summary of Information in the Application. The SLRA states that AMP B.2.1.3, Reactor Head Closure Stud Bolting Program, is an existing program that is consistent with the program elements in GALL-SLR Report AMP XI.M3, Reactor Head Closure Stud Bolting.
Audit Activities. During its audit, the staff reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the staff conducted its review of the applicants methodology and operating experience by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M3 Reactor Head Closure Stud Bolting Program Basis Document Revision 1 GEH-RPT-7480-315454-EB2-ISI D2R23 In-Service Inspection (ISI) Final Report Summary 2013 Fall Outage November 2013 7480-321205-EB2-ISI D2R24 In-Service Inspection (ISI) Final Report Summary 2015 Fall Outage November 2015 GEH-RPT-7480-324421-EB2-ISI D2R25 In-Service Inspection (ISI) Final Report Summary 2017 Fall Outage November 2017 D2R26-7480-199006-EB2-ISI D2R26 In-Service Inspection (ISI) Final Report Summary 2019 Fall Outage November 2019 GEH-RPT-7480-331077-EB2-ISI D2R27 Manual ISI Examinations Final Report November 2021 D3R27-7480-332222-EB3-ISI D3R27 In-Service Inspection (ISI) Final Report Summary 2022 Fall Outage November 2022 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
During the audit, the staff made the followingobservations:
The staff verified that the original DNPS reactor pressure vessel closure studs and nuts are fabricated from ASME SA-320, Grade L-43 alloy steel, which has a specified minimum yield strength of 105 ksi and a specified minimum tensile strength of 125 ksi.
6 The staff verified that available replacement studs and nuts are fabricated from ASME SA-540, Class 3, Grade B-24 and have an actual measured yield strength less than 150 ksi. The staff noted that replacement studs and nuts that have been installed since original construction are either original spares (SA-320, Grade L-43) or are fabricated from ASME SA-540, Class 3, Grade B-24.
The staff verified the Code of Record for DNPS is the 2017 Edition of ASME Boiler &
Pressure Vessel Section XI and that DNPS is in the 6th ISI interval with beginning and ending dates of January 2023 and January 2033, respectively.
The staff noted the extent and schedule for inspecting the reactor head closure studs, nuts, flange threads, bushings, and washers are consistent with those specified in ASME Code Section XI Table IWB-2500-1 for examination categories B-G-1 and B-P.
The staff verified in the examination results of the most recent ASME Code Section XI inservice inspection summary reports, listed in the table above, that there were no recordable indications for any reactor head closure studs, nuts, flange threads, washers, or bushings.
The staff verified that a manganese-phosphate coating was applied to the reactor head closure studs to improve galling resistance and to improve resistance to corrosion.
The staff also audited the description of the Reactor Head Closure Stud Bolting Program provided in the UFSAR supplement. The staff verified this descriptionisconsistent with the description provided in SRP-SLR.
SLRA AMP B.2.1.4, BWR Vessel ID Attachment Welds Summary of Information in the Application. The SLRA states that AMP, BWR Vessel ID Attachment Welds, is an existing program that is consistent with the program elements in GALL-SLR Report AMP XI.M4, BWR Vessel ID Attachment Welds.
Audit Activities. In addition to the OE documentation contained in the SLRA and ePortal, the staff observed the applicants search of its operating experience database using the keyword:
(cracking, stress corrosion)
The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M4 BWR Vessel ID Attachment Welds Revision 1 AR 04295315 D2R26 IVVI. Minor Change to Feedwater Sparger Bracket Wear November 11, 2019 AR 04535121 D3R27 IVVI: Feedwater Sparger End Bracket and Pin Wear November 6, 2022 BWRVIP-48-A BWR Vessel and Internals Project, Vessel ID Attachment Weld Inspection and Flaw Evaluation Guidelines Initial Revision BWRVIP-48 EPRI Proprietary. BWR Vessel and Internals Project, Vessel ID Attachment Weld Inspection and Flaw Evaluation Guidelines Revision 2
7 During the audit, the staff verified the applicants claim that the preventive actions, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP XI.M4. During the audit, the staff identified an exception associated with the scope of program, parameters monitored or inspected, detection of aging effects, monitoring and trending, program elements that was not identified by the applicant in its SLRA. The staff noted that the general framework of GALL-SLR Report AMP XI.M4 relies on the inspection guidelines contained in BWRVIP-48-A and ASME Section XI for reactor vessel attachments welds.
However, the staff noted that the applicants SLRA AMP relies on inspection guidelines contained in ASME Section XI and BWRVIP-48, Revision 2, (in lieu of BWRVIP-48-A) which has not received generic NRC approval. The staff will consider issuing an RAI in order to obtain the information necessary to determine whether these program elements impacted by the exception identified by the staff during its audit will provide adequate aging management of the RPV attachment welds.
The staff also audited the description of the SLRA AMP in the UFSAR supplement. The staff found that sufficient information was not available to determine whether the description provided in the UFSAR supplement was an adequate description of the SLRA AMP, due to the staff identified exception noted above. As discussed above, the staff will consider issuing an RAI in order to obtain the information necessary to verify the sufficiency of the UFSAR supplement program description.
SLRA AMP B.2.1.5, BWR Stress Corrosion Cracking Summary of Information in the Application. The SLRA states that AMP B.2.1.5, BWR Stress Corrosion Cracking is an existing program that is consistent with the program elements in GALL-SLR Report AMP XI.M7, BWR Stress Corrosion Cracking. To verify this claim of consistency, the staff audited the SLRA AMP.
Audit Activities. During its audit, the staff interviewed the applicants staff, and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. For the OE review, the applicant provided a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and evaluated the OE by reviewing the documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M7 Dresden Nuclear Power Station, Subsequent License Renewal Project, BWR Stress Corrosion Cracking, Program Basis Document Revision 1 06/18/2024 ER-DR-330-1001 Constellation Proprietary. Dresden Generation Station, Units 2 & 3, ISI Program Plan, Sixth Inspection Interval Revision 3 AR #04080012 AMP Effectiveness Review Revision 0 12/13/2018 AR #04071740 D2R25 - UT Indication - N20A Nozzle Weld 6 11/07/2017
8 Document Title Revision / Date WO #04709411 D2R25 - UT Indication - N20A Nozzle Weld 6 Assist Vendor in Performing Weld Overlay Nozzle N20A 11/11/2017 AR #04462211 D2R27 ISI Coverage Results 11/20/2021 AR #04705708 Unit 2 Entered OP-DR-108-111-1003 for Drywell Floor Drain Leakage 09/28/2023 ML24220A241 Dresden Nuclear Power Station - NRC Age-Related Degradation Inspection Report 05000237/2024010 and 05000249/2024010 08/09/2024 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding program elements in the GALL-SLR Report AMP.
The staff also audited the description of the SLRA AMP provided in the UFSAR supplement.
The staff verified this description is consistent with the description provided in the SRP-SLR.
SLRA AMP B.2.1.6, BWR Penetrations Summary of Information in the Application. The SLRA states that AMP B.2.1.6, BWR Penetrations, is an existing program that is consistent with the program elements in GALL-SLR Report AMP XI.M8, BWR Penetrations. To verify this claim of consistency, the staff audited the SLRA AMP.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation referenced in the SLRA and provided by the applicant via the ePortal. For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M8 Aging Management Program (AMP) Program Basis Document Revision 1 November 2023 AR 04080012-08 AMP Effectiveness Review Revision 0 December 2018 WO 50011222 Reactor Vessel System Leakage Test February 2022 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
9 The staff also audited the description of the SLRA BWR Penetrations provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.7, BWR Vessel Internals Summary of Information in the Application. The SLRA states that AMP B.2.1.7, BWR Vessel Internals, is an existing program with enhancements that will be consistent with the program elements in GALL-SLR Report AMP XI.M9, BWR Vessel Internals. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the existing implementing procedures.
Audit Activities. The staff took note of the OE documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M9 Program Basis Document - BWR Vessel Internals Revision 1 BWRVIP-180 EPRI Proprietary. Access Hole Cover Inspection and Flaw Evaluation Guidelines Revision 1 BWRVIP Letter 2021-030 (ML21084A164)
Potential Non-Conservatism in EPRI Report, BWRVIP-100, Rev.
1-A, 3002008388 and Impacted BWRVIP Reports March 22, 2021 BWRVIP-139 Steam Dryer Inspection and Flaw Evaluation Guidelines Revision 1-A IR 04406225 Pot. Part 21: EPRI BWRVIP-235 DLL Potential Non-Conservatism IR 04410934 Updated Pot Part 21: BWRVIP-235 and Other Impacted EPRI Docs During the audit, the staff verified the applicants claim that the preventive actions, parameters monitored or inspected, detection of aging effects, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding elements of the GALL-SLR Report AMP after implementation of the identified enhancements.
The staff found that for the scope of program and monitoring and trending program elements, sufficient information was not available to determine whether they were consistent with the corresponding program elements of the GALL-SLR Report AMP. The staff will consider issuing an RAI to obtain the information necessary to verify whether these program elements are consistent with the corresponding program elements of the GALL-SLR Report AMP. During the audit, the staff made the following observations:
The staff noted that the applicant intends to utilize BWRVIP-76 Revision 1-A, BWRVIP-25 Revision 1-A, BWRVIP-18 Revision 2-A, BWRVIP-41 Revision 4-A, and BWRVIP-183 Revision A in lieu of the revisions of those documents cited in GALL-SLR. These revisions of each report are NRC approved for generic use and are therefore acceptable
10 for use as part of the BWR Vessel Internals program. However, they are a staff identified exception to the scope of program program element in the GALL-SLR Report AMP.
The staff noted that the applicant intends to utilize BWRVIP-180 Revision 1 in lieu of BWRVIP-180 Revision 0, which is cited in GALL-SLR, but provides no discussion regarding the technical acceptability of Revision 1 or detailing the differences between the revision. The staff will consider issuing an RAI to obtain the information necessary to determine the sufficiency of this aspect of the scope of program program element.
The GALL-SLR recommends the use of BWRVIP-02-A Revision 2 for repair design criteria of the core shroud. The staff noted that the SLRA cites the use of BWRVIP-02-A, while the program basis document (DR-PBD-AMP-XI.M9 Revision 1) specifies the use of BWRVIP-02 Revision 2-A. This appears to be an inconsistency in nomenclature, rather than a technical change, but the staff will consider issuing an RAI to obtain clarity on which revision of BWRVIP-02 is being specified.
The GALL-SLR recommends the use of BWRVIP-41 and BWRVIP-138 Revision 1-A for inspection and evaluation guidelines for the jet pump assembly. The SLRA only specifies the use of BWRVIP-41 for this application and doesnt mention BWRVIP-138 Revision 1-A. The program basis document (DR-PBD-AMP-XI.M9 Revision 1) does discuss the use of BWRVIP-138 so the lack of discussion about BWRVIP-138 in the SLRA appears to be an oversight. The staff will consider issuing an RAI to obtain clarity on the use of BWRVIP-138 as part of the applicants BWR Vessel Internals AMP.
The GALL-SLR recommends the use of BWRVIP-100-A for flaw evaluation methodologies and fracture toughness data for stainless steel core shroud exposed to neutron irradiation. Appendix C of the SLRA specifies the use of BWRVIP-100-A in response to Applicant Action Item 4 of BWRVIP-76 Revision 1-A. On the other hand, Appendix C of the SLRA also specifies the use of BWRVIP-100, Revision 1-A in response to Applicant Action Item 8 of BWRVIP-76 Revision 1-A. Thus, its not clear to the staff whether the applicant is using BWRVIP-100-A or BWRVIP-100, Revision 1-A.
The staff will consider issuing an RAI to address the inconsistency associated with the revision of BWRVIP-100 in the responses to the applicant action items for BWRVIP-76 Revision 1-A.
Additionally, BWRVIP-100 Revision 1-A was subject to a 10 CFR Part 21 notice (ML21084A165) due to non-conservatism on fracture toughness of reactor vessel shell material. During its audit, the staff confirmed (IR 04406225 and IR 04410934) that a fleetwide assessment was performed to address the 10 CFR Part 21 notice, which determined that DNPS, Units 2 and 3, were not impacted.
The staff also audited the description of the SLRA BWR Vessel Internals provided in the UFSAR supplement. The staff found that sufficient information was not available to determine whether the description provided in the UFSAR supplement was an adequate description of the SLRA BWR Vessel Internals Program. The staff will consider issuing an RAI to obtain the information necessary to verify the sufficiency of the UFSAR supplement program description regarding the observation noted below.
During the audit, the staff made the following observations:
11 The staff noted that the UFSAR supplement generically discusses the use of BWRVIPs but only specifically mentions BWRVIP-41 Revision 4-A in relation to Enhancement 1 of the BWR Vessel Internals AMP. BWRVIP-315-A (ML23251A069) Section 4.5.1 Limitation 2 states:
owners submitting an application for operation beyond 60 years (e.g., an SLRA in the U.S.)
should either commit to implementing a future version of BWRVIP-47 that addresses extended operations or propose a set of plant-specific activities to manage age-related degradation of CRGTs.
In response to that limitation, Appendix C of the SLRA states:
new or revised inspection recommendations in BWRVIP-47 are required to be implemented in accordance with BWRVIP-94-R4: BWR Vessel and Internals Project, Program Implementation Guide and NEI 03-08, Guideline for the Management of Material Issues. Future revisions of BWRVIP-47 that address DNPS extended operations will be implemented as applicable.
BWRVIP-94 and NEI 03-08 are not NRC approved documents, and their invocation does not create a regulatory mechanism regarding the implementation of a future revision of BWRVIP-47. The staff will consider asking an RAI to request how a regulatory mechanism to ensure implementation of the future revision of BWRVIP-47 can be introduced to the SRLA.
SLRA AMP B.2.1.8, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS)
Summary of Information in the Application. The SLRA states that AMP B.2.1.8, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS), is a new program that is consistent with the program elements in GALL-SLR Report AMP XI.M12, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS). To verify this claim of consistency, the staff audited the SLRA AMP.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. The staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal. The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M12 Program Basis Document - Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS)
Revision 1 /
12/2023 WO 00318863, WO 00989303, WO 01772080 Reactor Recirculation Pump Internals Removal/Replacement for Dresden Nuclear Power Station 2004, 2007, 2019 ER-AA-330-1007 Constellation Proprietary. Application of ASME Section XI Code Cases in Accordance with 10 CFR 50.55a and Regulatory Guide 1.147 Revision 4
12 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
During the audit, the staff made the following observation:
During breakout sessions, the applicant stated that the applicability of ASME Code Case N-824, Ultrasonic Examination of Cast Austenitic Piping Welds from the Outside Surface,Section XI, is limited to the 2001 Edition through 2013 Edition of the ASME Code,Section XI. The Dresden code of record is the 2017 Edition of the ASME Code,Section XI. Therefore, the requirements of the 2017 Edition of the ASME Code,Section XI with provisions in 10 CFR 50.55a are applied to the UT of CASS.
The staff also audited the description of the SLRA Thermal Aging Embrittlement of CASS provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.9, Flow-Accelerated Corrosion Summary of Information in the Application. The SLRA states that AMP B.2.1.9, Flow-Accelerated Corrosion, is an existing program with an enhancement that will be consistent with the program elements in GALL-SLR Report AMP XI.M17, Flow-Accelerated Corrosion. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M17 Flow-Accelerated Corrosion (a Program Basis Document)
Revision 1 ER-AA-430 Constellation Proprietary. Conduct of Flow Accelerated Corrosion Activities Revision 10 ER-AA-430-1001 Constellation Proprietary. Guidelines for Flow Accelerated Corrosion Activities Revision 15 ER-AA-430-1002 Constellation Proprietary. Feedwater Heater Shell Inspection for Detection of Flow Accelerated Corrosion Revision 7 ER-AA-430-1004 Constellation Proprietary. Erosion in Piping and Components (EPC) Guide Revision 5 AR #04080012 AMP Effectiveness Review 06/01/2018 AR #2723540-04 2019 Self-Assessment of FAC/EPC Program Revision 2 AR #04293982 Component 2SH51A Below Code Min Wall Thickness 11/02/2019 AR #04071361 Wall Thinning of the 2A1 FWH Shell 11/06/2017 EC 621080 Feedwater Heater Minimum Wall Thickness Criteria 11/13/2017 M-4036 Piping Isometric Reactor Drain Line (a drawing)
Revision C AR #00860977 BWRVIP-205, Bottom Head Drain Line I&E Guideline 12/29/2008
13 WO #01202827 NDE Bottom Head Drain Line Per BWRVIP-205 10/24/2011 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding elements of the GALL-SLR Report AMP after implementation of the identified enhancement.
During the audit, the staff made the following observations:
The staff reviewed drawings and documents on the Portal related to the design and inspection of the Dresden Unit 2 reactor vessel bottom head drain line. The staff observed that, immediately downstream of the bottom head drain, there is approximately thirteen feet of carbon steel piping (including two carbon steel elbows) followed by approximately fifty feet of stainless steel piping, which empties into the reactor water cleanup system piping. The staff observed that the carbon steel elbows were socket welded rather than butt welded. The staff did not observe any expanders or reducers in the carbon steel portion of the bottom head drain line. The staff notes that for the two material types represented in the bottom head drain line, carbon steel is susceptible to FAC, but stainless steel is not.
The staff also audited the description of the SLRA Flow-Accelerated Corrosion program provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.10, Bolting Integrity Summary of Information in the Application. The SLRA states that AMP B.2.1.10, Bolting Integrity, is an existing program with enhancements, and one exception, that will be consistent with the program elements in GALL-SLR Report AMP XI.M18, Bolting Integrity. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M18 Program Basis Document - Bolting Integrity Revision 1 N/A Dresden Nuclear Power Station Updated Final Safety Analysis Report (UFSAR); NRC Docket Nos. STN 50-237 (Unit 2) and 50-249 (Unit 3)
Revision 15
14 Document Title Revision / Date CC-AA-102 Constellation Proprietary. Design Input and Configuration Change Impact Screening Revision 35 CC-AA-103-1001 Constellation Proprietary. Design Resource Manual Revision 15 MA-AA-736-600 Constellation Proprietary. Torquing and Tightening of Bolted Connections Revision 15 ER-AA-2030 Constellation Proprietary. Conduct of Equipment Reliability Manual Revision 31 ER-AA-330-001 Constellation Proprietary.Section XI Pressure Testing Revision 20 MA-AA-410 Constellation Proprietary. Bolting Integrity Aging Management Program Revision 3 ER-AA-5400-1002 Constellation Proprietary. Underground Piping and Tank Examination Guide Revision 10 DTS 1600-36 Emergency Core Cooling System (ECCS) Suction Strainer Inspection Criteria Revision 9 NO-AA-10 Constellation Proprietary. Quality Assurance Topical Report (QATR)
Revision 99 PES-S-010 Fasteners Revision 5 PI-AA-120 Constellation Proprietary. Issue Identification and Screening Process Revision 13 PI-AA-125 Constellation Proprietary. Corrective Action Program (CAP)
Procedure Revision 9 DMP 3900-02 Service Water Pump (With Lube Waer Strainers) Removal and Installation Revision 13 DMP 3900-06 Upgraded Service Water Pump (With Process Lubed Bearings)
Removal and Installation Revision 3 AR 01500095 Bolt Connecting Valve Bonnet to Yoke Loose on 2-3399-729 04/10/2013 AR 04110057 Unit 3 HPCI Turbine-CV Rack Steam Leak at Flange Mating Surface 03/01/2018 AR 04130464 3B Inst Air Dryer Filter Flow Meter Pipe Flange Loose 04/24/2018 AR 04297362 Bolted Connection 20 DPM Leak on 2B LPCI Room Cooler 11/14/2019 AR 04382043 D3R26: FME: ECCS Suction Strainer Inspection Results 11/03/2020 AR 4080012-08, 20, 22 Aging Management Program (AMP) Effectiveness Review Revision 0 During the audit, the staff verified the applicants claim that the scope of program, parameters monitored or inspected, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP. In addition, the staff found that for the preventive actions, and detection of aging effects program elements, sufficient information was not available to verify whether they were consistent with the corresponding program elements of the GALL-SLR Report AMP. The staff will consider issuing RAIs or use a voluntary SLRA supplement in
15 order to obtain the information necessary to verify whether these program elements are consistent with the corresponding program elements of the GALL-SLR Report AMP.
During the audit, the staff made the following observations:
The staff noted in SLRA Section B.2.1.10 that it is not clear why Enhancement 5 is needed to perform volumetric examination in accordance with ASME Section XI, Table IWB-2500-01, Examination Category B-G-1 for high-strength bolting greater than 2 inches in diameter, when high-strength bolting material is not used for closure bolting with bolt diameters greater than 2 inches on pressure-retaining components.
The staff noted that an AMR line item for the Traveling Screen Bolting component may need to be added in SLRA Table 3.3.2-12.
The staff noted in SLRA Section B.2.1.10 that the guidance document that Enhancement 1 is based on is inconsistent with those specified in the program basis document.
The staff noted in SLRA Section B.2.1.10 that it is not clear whether the alternative inspections that are performed if the minimum sample size is not achieved for Enhancement 2 are applicable to Traveling Water Screens bolting.
The staff noted that AMR item 3.4.1-007 in SLRA Table 3.4.1 is shown as being consistent with NUREG-2191 with exceptions but the AMR item may be inapplicable.
The staff will consider issuing RAIs or use a voluntary SLRA supplement to obtain the information necessary to make its findings regarding the issues identified in the observations above.
The staff also audited the description of the SLRA Bolting Integrity provided in the UFSAR supplement Section A.2.1.10. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.11, Open Cycle Cooling Water System Summary of Information in the Application. The SLRA states that AMP B.2.1.11, Open Cycle Cooling Water System, is an existing program that, with enhancements, will be consistent with the program elements in GALL-SLR Report AMP XI.M20, Open Cycle Cooling Water System.
At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M20 Open-Cycle Cooling Water Revision 1
16 4080012-02 AMP Effectiveness Review for Open-Cycle Cooling Water 09/14/2018 AR 02530306 Unit 2 Containment Cooling Service Water piping replacement 07/20/2015 AR 02433986 3A Low Pressure Coolant Injection Heat Exchanger Performance Trend 01/07/2015 AR 04049510 3B Low Pressure Coolant Injection Heat Exchanger Inspection 09/06/2017 AR 02556224 U3 Division 1 Containment Coolant Service Water Discharge Line Leak 09/16/2015 WO 01861885 Work Order for U3 Div 1 Containment Coolant Service Water Discharge Line Leak 09/18/2015 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding element of the GALL-SLR Report AMP, after implementation of the identified enhancements.
The staff also audited the description of the Open Cycle Cooling Water System AMP provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.12, Closed Treated Water Systems Summary of Information in the Application. The SLRA states that AMP B.2.1.12, Closed Treated Water Systems, is an existing program that, with enhancements, will be consistent with the program elements in GALL-SLR Report AMP XI.M21A, Closed Treated Water Systems, as modified by SLR-ISG-2021-02-MECHANICAL. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M21A Closed Treated Water Systems Revision 1 AR 04080012-03 AMP Effectiveness Review for Closed Treated Water Systems 10/25/2018 AR 02681785 U3 EDG Jacketed Cooling Water Action Level 1 for pH 06/15/2016 AR 04397520 3A Turbine Building Closed Cooling Water Heat Exchanger Eddy Current Test Results 01/22/2021 AR 04557716 Elevated Iron and Copper in U2 EDGJCW System 02/27/2023
17 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding element of the GALL-SLR Report AMP, after implementation of the identified enhancements.
The staff also audited the description of the Closed Treated Water Systems AMP provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.13, Inspection of Overhead Heavy Load and Light Load (Related to Refueling) Handling Systems Summary of Information in the Application. The SLRA states that AMP B.2.1.13, Inspection of Overhead Heavy Load and Light Load (Related to Refueling) Handling Systems, is an existing program that is consistent with the program elements in GALL-SLR Report AMP XI.M23, Inspection of Overhead Heavy Load and Light Load (Related to Refueling) Handling Systems.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M23 Program Basis Document - Inspection of Overhead Heavy Load and Light Load (Related to Refueling) Handling Systems Revision 1 N/A Dresden Nuclear Power Station Updated Final Safety Analysis Report (UFSAR); NRC Docket Nos. STN 50-237 (Unit 2) and 50-249 (Unit 3)
Revision 15 DMS 0800-01 Unit 2(3) Refueling Platform Gantry Crane Pre-Refueling Mechanical Inspection and Preventative Maintenance Revision 15 DMS 5800-05 Jib, Monorail, and Underhung Cranes without Integral Hoisting Mechanisms, Annual Inspection and Preventive Maintenance Revision 25 DMS 5800-10 Unit 2(3) Refueling Platform Gantry Crane and Integral Hoisting Equipment, Monthly Inspection and Preventive Maintenance Revision 7 DMS 5800-11 Unit 2(3) Refueling Platform Gantry Crane Annual (OSHA)
Inspection Revision 1 MA-AA-716-021 Constellation Proprietary. Rigging and Lifting Program Revision 38 MA-DR-MM-5-58001 Constellation Proprietary. Visual Inspection and Preventive Maintenance of Jib, Monorail, and Underhung Cranes with Integral Hoisting Mechanisms Revision 23 MA-DR-MM-5-58003 Constellation Proprietary. Visual Inspection and Preventive Maintenance of Unit 1, Unit2, Unit 3, and Unit 2-3 Overhead and Gantry Cranes Revision 22
18 Document Title Revision / Date AR 02445156 RX Building Overhead Crane Annual Inspection Discrepancies 01/30/2015 AR 4080012-04 Aging Management Program (AMP) Effectiveness Review -
Dresden - Inspection of Overhead Heavy / Light Load Systems Revision 1 AR 04104302 Recommendations Identified during RXB Crane Inspection 02/15/2018 AR 04185334 U2 Refueling Platform Main Hoist Rail Roller Degraded 10/19/2018 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
During the audit, the staff made the following observations:
The staff noted that there was a lack of clarity in SLRA Section B.2.1.13 regarding how many overhead heavy load and light load handling systems are in the scope of the SLRA AMP.
The staff noted that the list of overhead heavy load and light load handling system components is not clearly presented in SLRA Section 2.3.3.5.
The staff noted in SLRA Table 3.3.2-5 that the line items citing AMR item 3.3.1-052 do not consider all the aging effects associated with the AMR item.
The staff will consider issuing RAIs or use a voluntary SLRA supplement to obtain the information necessary to make its findings regarding the issues identified in the observations above.
The staff also audited the description of the SLRA AMP Inspection of Overhead Heavy Load and Light Load (Related to Refueling) Handling Systems provided in the UFSAR supplement Section A.2.1.13. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.14, Compressed Air Monitoring Summary of Information in the Application. The SLRA states that AMP B.2.1.14, Compressed Air Monitoring, is an existing program with an enhancement and an exception that will be consistent with the program elements in GALL-SLR Report AMP XI.M24, Compressed Air Monitoring. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. During its audit, the staff reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal. The table below lists the documents that were reviewed by the staff and
19 were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date WO:04788507 00005897-03 PMNS, D3 NDD PM IAC 3B Dryer Desiccant Replacement, E:3-4718, N/A, D20 02/11/22 AMP Effectiveness Review Form Aging Management Program Effectiveness Review 02/23/2018 AR 04473439 3B IAC Air Dryer Desiccant Pink 01/23/2021 Project Number 00472576 Quarterly Instrument Air Performed 10/10/2016 10/13/2016 DR-PBD-AMP-XI.M24 Program Basis Document Compressed Air Monitoring Revision 1 During the audit, the staff verified the applicants claim that the scope of program, parameters monitored or inspected, detection of aging effects, and monitoring and trending program elements of the SLRA AMP will be consistent with the corresponding elements of the GALL-SLRReport AMP after implementation of the identified enhancement.
The staff also verified the applicants claim that aspects of the preventive actions, acceptance criteria, and corrective actions program elements not associated with the exception identified in the SLRAare consistent with the corresponding program elements inthe GALL-SLRReport AMP.
The staff also audited the description of the SLRA AMP Compressed Air Monitoring program provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.15, Fire Protection Summary of Information in the Application. The SLRA states that AMP B.2.1.15, Fire Protection, is an existing program that is consistent with the program elements in GALL-SLR Report AMP XI.M26, Fire Protection. To verify this claim of consistency, the staff audited the SLRA AMP.
Audit Activities. The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title/Description Revision / Date DR-PBD-AMP-XI.M26 Program Basis Document - Fire Protection Revision 2 DFPP 4175-01 Fire Barrier Integrity and Maintenance Revision 25 DFPS 4145-02 Auxiliary Electric Equipment Room Manual Cardox System Revision 24
20 Document Title/Description Revision / Date DFPS 4175-02 Operating Fire Stop/Break Surveillance Revision 35 DFPS 4175-03 Shutdown Fire Stop Surveillance Revision 27 DFPS 4175-04 Auxiliary Electrical Equipment Room Fire Resistive Structural Steel and Cable Coating Surveillance Revision 12 DFPS 4175-07 Fire Door/Oil Spill Barrier Surveillance Revision 39 DFPS 4175-09 Fire Damper Visual Inspection Revision 20 DFPS 4175-11 Appendix R Cable/Conduit Firewrap Inspection Revision 12 DFPS 4175-12 Fire Resistive Structural Steel Coating Surveillance Revision 19 DFPS 4195-02 Auxiliary Electrical Equipment Room Halon System Test Revision 28 AR 4080012-23 Aging Management Program Effectiveness Review - Fire Protection and Fire Water System Revision 1 AR 02638773 Degraded Fire Penetration March 10, 2016 AR 04110936 Fire Door Failed 18 Month Surveillance March 3, 2018 AR 04461231 Inoperable Fire Door November 16, 2021 WO 01737330 18 Month Fire Stop/Break Surveillance December 22, 2015 WO 05205950-01 Repair Inoperable Fire Door November 17, 2021 AR 01514526 Fire Damper Slow to Close May 16, 2013 AR 01551302 Inoperable Fire Barrier Installed in Penetration August 27, 2013 AR 01552144 Compromised Fire Rated Wall August 29, 2013 AR 01642745 Inoperable Fire Barrier for Penetration April 3, 2014 AR 02547428 Fire Wrap Not Installed Correctly August 27, 2015 AR 02586485 Inoperable Fire Barrier Duct Covers November 12, 2015 AR 03996053 Large Piece of Drywall Missing from Wall April 9, 2017 AR 04308456 Broken Concrete Behind Fire Hose Cover January 7, 2020 WO 01919341-01 Repair Degraded Fire Penetration December 5, 2018 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and
21 trending, acceptance, and corrective actions program elements of the SLRA AMP were consistent with the corresponding elements of the GALL-SLR Report AMP.
The staff also audited the description of the SLRA Fire Protection program in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.16, Fire Water System Summary of Information in the Application. The SLRA states that AMP B.2.1.16, Fire Water System, is an existing program with three exceptions and six enhancements that will be consistent with the program elements in GALL-SLR Report AMP XI.M27, Fire Water System.
To verify this claim of consistency, the staff audited the SLRA AMP. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the description of the enhancements in the SLRA and the applicants basis document.
Audit Activities. The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title/Description Revision / Date DR-PBD-AMP-XI.M27 Program Basis Document - Fire Water System Revision 1 DFPP-4100-04 Fire Header Flushing Revision 03 DFPS 4113-01 Fire Hose station Valve Operability Test Revision 24 DFPS 4114-02 Unit 2 Fire System Inspection Revision 33 DFPS 4114-03 Unit 3 and 2/3 Radwaste Fire System Inspection Revision 30 DFPS 4114-05 Fire Hose Inspection/Service Test Revision 43 DFPS 4114-06 Fire System Yard Loop Inspection Revision 50 DFPS 4114-10 Fire System Outside Yard Loop Inspection Revision 24 DFPS 4123-08 Fire Water System Flow Test Revision 35 DFPS 4123-09 Unit 2/3 Non-Accessible Valve Position Verification Revision 08 DFPS 4123-13 Aboveground Fire Water System Flow Test Revision 02 DFPS 4125-01 Fire System Yard and Interior Loop Flush Revision 27 DFPS 4125-02 Fire Hydrant Flushing and Lubrication Revision 17
22 Document Title/Description Revision / Date DFPS 4125-03 Fire System Yard Loop Flush Revision 12 DFPS 4132-01 Verification of Unit 1, 2, & 3 Sprinkler System Integrity Revision 24 DFPS 4132-02 Refuel/Operating Cycle Verification of Unit 2 Sprinkler Systems Integrity Revision 24 DFPS 4133-05 Fire Water Supply Drain Test Revision 26 DFPS 4133-09 Transformer 3(31) Deluge System Flow Test Revision 18 DFPS 4134-01 Refuel Operating Cycle Hydrogen Seal Oil Unit Deluge Inspection (Unit 3 Only)
Revision 13 AR01351057 Fire Protection Pipe Appears to be Leaking Thru-Wall 3/30/2012 AR01363364 Fire Piping Leak 5/07/2012 AR01507576 Through Wall Pipe Leak on U3 Fire Header 4/28/2013 AR01535406 Through Wall Leak on Pipe Between Fire Hydrant and Hose Cabinet Isolation Valve 7/14/2013 AR01538445 Fire Protection Pipe Leakage 7/2/2013 AR01599721 Review of actions related to NRC Information Notice 2013-006 12/20/2013 AR02504548 Pipe Lining in Fire Hydrant May 22, 2015 AR02522833 Fire Header Piping Leak July 1, 2015 AR02522849 Fire Header Piping Leak July 1, 2015 AR04341513 High Pressure Drop During Fire Protection Yard Loop Test May 6, 2020 AR01359458 Pre-action System Walkdown - Unit 2 Reactor Building Equipment Hatchway and Stairwell April 27, 2012 AR01359471 Pre-action System Walkdown - Unit 3 Reactor Building Equipment Hatchway April 27, 2012 AR01359541 Pre-action System Walkdown - Unit 2 HPCI Room April 27, 2012 AR01359547 Pre-action System Walkdown - Unit 3 HPCI Room April 27, 2012 AR01359654 Pre-action System Walkdown - Unit 2 A Instrument Air Compressor Area April 27, 2012 AR01359722 Pre-action System Walkdown - Unit 2 Mezzanine Cable Floor Area April 27, 2012 TRM 3.7.i Fire Water Supply System Revision 0 TRM 3.7.J Water Suppression Systems Revision 95
23 Document Title/Description Revision / Date TRM 3.7.l Fire Hose Stations Revision 101 Technical Evaluation to Justify Extending Inspection Frequency 2014 AR04430825 Hole in 2A Traveling Screen June 22, 2021 DTS 3900-07 Crib House/Intake Structure Inspections Revision 14 DMP 3900-04 Inspect and Clean Unit 2/3 Fire Pump Bay (Bay 13) and Downstream Screens Revision 03 MA-DR-MM-5-44001 Constellation Proprietary. Traveling Screen Preventive Maintenance Revision 07 DOP 4400-03 Unit 2(3) Traveling Water Screens Revision 19 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance, and corrective actions program elements of the SLRA AMP were consistent with the corresponding elements of the GALL-SLR Report AMP or will be consistent after implementation of the identified enhancements.
The staff also audited the description of the SLRA Fire Water System program in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.17, Outdoor and Large Atmospheric Metallic Storage Tanks Summary of Information in the Application. The SLRA states that AMP B.2.1.1.7, Outdoor and Large Atmospheric Metallic Storage Tanks, is an existing program with enhancements that will be consistent with the program elements in GALL-SLR Report AMP XI.M29, Outdoor and Large Atmospheric Metallic Storage Tanks. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. The table below lists the documents that were reviewed by the staff and were found relevant to the Outdoor and Large Atmospheric Metallic Storage Tanks program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M29 Program Basis Document Outdoor and Large Atmospheric Metallic Storage Tanks Revision 1 WO: 1745402 Elevated Tritium Results from Monitoring Well MD-11 Part 5 10/19/2022 IR 01680577 Dresden A CST (2/3 - 3303-A) is Vulnerable to Degradation 06/07/2014 AR 01131148 Nuclear Event Report (NER) NC-10-056 10/26/2010
24 Document Title Revision / Date AR-00902395 2/3 A-CST Gasket Needs to be Repaired/Replaced 04/03/2009 AR-00902383 2/3 B CST Tank Bottom has a Gap Between the Tank and Ground 04/03/2009 WO-01758124 2/3 B CST Tank Bottom has a Gap Between the Tank and Ground 04/04/2009 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding element(s) of the GALL-LRReport AMP after implementation of the identified enhancements.
The staff also audited the description of the SLRA Outdoor and Large Atmospheric Metallic Storage Tanks provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.18, Fuel Oil Chemistry Summary of Information in the Application. The SLRA states that AMP B.2.1.18, Fuel Oil Chemistry, is an existing program with enhancements that will be consistent with the program elements in GALL-SLR Report AMP XI.M30, Fuel Oil Chemistry. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. During its audit, the staff reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the Fuel Oil Chemistry program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DRP-PBD-AMP-XI.M30 Program Basis Document GALL-SLR Program XI.M30 Fuel Oil Chemistry Revision 1 05/06/2024 01668264 00012149-01, COM, D2/3 10Y COM Clean B Isol Cond M/U Diesel Fuel Oil Day 08/26/2018 AR-101522-30 Aging Management Program (AMP) Effectiveness Review 06/28/2018 AR-02619194 Pending Fuel Oil Combustible Requirements for 2017 01/29/2016 WO-01449886 D 2/3 10Y Com Clean A Isol Cond M/U Diesel Fuel Oil Day Tank, E:2/3-5215-A Tank T05 01/29/2016
25 AR 01169720 2/3 EDG Fuel Storage Tank Sample Elevated Moisture 03/29/2012 EC Eval 366134 EC Evaluation 366134 Evaluate Regulator Issues for EDG Fuel Oil Storage Tank Wall Thickness Measurements Revision 0 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding element(s) of the GALL-LRReport AMP after implementation of the identified enhancements.
The staff also audited the description of the SLRA AMP provided in the UFSAR supplement.
The staff verified this description is consistent with the description provided in the SRP-SLR.
SLRA AMP B.2.1.19, Reactor Vessel Material Surveillance Summary of Information in the Application. The SLRA states that AMP XI.M31, Reactor Vessel Material Surveillance, is an existing program with one enhancement that is consistent with the program elements in GALL-SLR Report AMP XI.M31, Reactor Vessel Material Surveillance.
Audit Activities. The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date N/A Dresden Nuclear Power Station, Units 2 and 3 Subsequent License Renewal Application April 2024 BWRVIP-321 BWR Vessel and Internals Project, Plan for Extension of the BWR Integrated Surveillance Program (ISP) through the Second License Renewal (SLR)
Revision 1-A DR-PBD-AMP-XI.M31 Reactor Vessel Material Surveillance Rev 1 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report after implementation of the identified enhancements.
During the audit, the staff made the following observation:
The licensees program uses the Integrated Surveillance Program described in BWRVIP-321 Revision 1-A to maintain compliance with 10 CFR 50 Appendix H during the subsequent period of extended operation.
The staff also audited the description of the SLRA AMP Reactor Vessel Material Surveillance Program provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
26 SLRA AMP B.2.1.20, One-Time Inspection Summary of Information in the Application. The SLRA states that AMP B.2.1.20, One-Time Inspection, is a new program that will be consistent with the program elements in GALL-SLR Report AMP XI.M32, One-Time Inspection. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this new program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M32 One-Time Inspection [program basis document]
Revision 1 0000377462 Evaluate UT Thickness Reading for U2 Standby Liquid Control Tank 2-1103 Wall Thickness Measurement 10/26/2009 0000383515 Evaluate Wall Thickness for Unit 3 Standby Liquid Control Tank 3-1103 04/27/2011 00727036 Perform a UT of Unit 2 SBLC Storage Tank for License Renewal 01/28/2008 01316853 COM UT ECCS Suction Strainer Flange at Penetration 12/06/2013 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report XI.M32, One-Time Inspection.
The staff also audited the description of the SLRA Section A.2.1.20, One-Time Inspection program provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.21, Selective Leaching Summary of Information in the Application. The SLRA states that AMP B.2.1.21, Selective Leaching, is a new program with an exception that will be consistent with the program elements in GALL-SLR Report AMP XI.M33, Selective Leaching. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this new program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
27 Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M33 Program Basis Document Selective Leaching, GALL-SLR Program XI.M33 - Selective Leaching Revision 1 ER-AA-700-401 Constellation Proprietary. Selective Leaching Aging Management Revision 4 N/A Dresden Station Aging Management Program Results Book B.1.24 Selective Leaching 09/14/2010 During the audit, the staff verified the applicants claim that the scope of program and preventive actions program elements of the SLRA AMP will be consistent with the corresponding elements of the GALL-SLR Report AMP. In addition, the staff found that for the parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements, sufficient information was not available to determine whether they were consistent with the corresponding program elements of the GALL-SLR Report AMP. The staff will consider issuing RAIs in order to obtain the information necessary to verify whether these program elements are consistent with the corresponding program elements of the GALL-SLR Report AMP.
The staff also audited the description of the SLRA Selective Leaching program provided in the UFSAR supplement. The staff found that sufficient information was not available to determine whether the description provided in the UFSAR supplement was an adequate description of the SLRA Selective Leaching program. The staff will consider issuing RAIs in order to obtain the information necessary to verify the sufficiency of the UFSAR supplement program description.
SLRA AMP B.2.1.22, ASME Code Class 1 Small-Bore Piping Program Summary of Information in the Application. The SLRA states that AMP B.2.1.22, ASME Code Class 1 Small-Bore Piping is a new condition monitoring program that is consistent with the program elements in GALL-SLR Report AMP XI.M35, ASME Code Class 1 Small-Bore Piping.
To verify this claim of consistency, the staff audited the SLRA AMP.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant provided a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and evaluated the OE by reviewing the documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M35 Dresden Nuclear Power Station, Units 2 and 3 Subsequent License Renewal Project, ASME Code Class 1 Small-Bore Piping, PROGRAM BASIS DOCUMENT Revision 2 09/03/2024
28 Document Title Revision / Date AR# 00134459 Unit 3 Reactor Recirculation Sensing Line Leak 12/07/2002 AR# 00134459-41 Root Cause Report - Reactor Recirculation Loop A Low Pressure Flow Venturi Differential Pressure Sensing line Socket Weld High Cycle Fatigue Failure due to Mechanically Induced Residual Pipe Stresses Coupled with Sensing Line Vibration Caused by Resonance Frequency with the RR Pump Speed Revision 2 05/13/2003 EC 363796 Vibration Evaluation - Unit 3 Reactor Recirculation Instrument Sensing Lines Revision 0 AR# 04200026 Instrument Line to 2-3241-C1, -C2 Vibration Levels Evaluated 12/04/2018 AR# 04368036 WR for Weld Cap on 3A Reactor Recirculation Drain Line 09/08/2020 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
The staff also audited the description of the SLRA AMP ASME Code Class 1 Small-Bore Piping provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in SRP-SLR.
SLRA AMP B.2.1.23, External Surfaces Monitoring of Mechanical Components Summary of Information in the Application. The SLRA states that AMP B.2.1.23, External Surfaces Monitoring of Mechanical Components, is a new program that will be consistent with the program elements in GALL-SLR Report AMP XI.M36, External Surfaces Monitoring of Mechanical Components. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this new program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M36 External Surfaces Monitoring of Mechanical Components Revision 1 AR 4501773 Surface rust on discharge piping of U2E LPCI Room sump pump 05/24/2022 AR 1178461 SW pipe insulation cover corrosion 02/22/2011 WR 359694 SW pipe insulation cover replacement 02/23/2011 AR 03981971 3A CW expansion joint replacement 03/06/2017
29 WR 4829704 3A CW expansion joint replacement 11/23/2022 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding element of the GALL-SLR Report AMP, after implementation of the identified enhancements.
The staff also audited the description of the External Surfaces Monitoring of Mechanical Components AMP provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.24, Inspection of Internal Surfaces in Miscellaneous Piping and Ducting Components Summary of Information in the Application. The SLRA states that AMP B.2.1.24, Inspection of Internal Surfaces in Miscellaneous Piping and Ducting Components, is a new program that will be consistent with the program elements in GALL-SLR Report AMP XI.M38, Inspection of Internal Surfaces in Miscellaneous Piping and Ducting Components. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this new program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M38 Inspection of Internal Surfaces in Miscellaneous Piping and Ducting Components Revision 1 AR 04514409-75-06 AMP Effectiveness Review for Periodic Inspection of Ventilation System Elastomers Revision 1 AR 04514409-75-19 AMP Effectiveness Review for Periodic Inspection of Plant Heating Systems Revision 1 WO 1913762 Work order for repair of U2 reactor building ventilation fan plenum 04/14/2020 AR 02650681 U2 Reactor building ventilation fan plenum corrosion observed during inspection 04/04/2016 WO 913872 Work order for repair of U2 reactor building ventilation fan plenum 01/12/2009 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding element of the GALL-SLR Report AMP.
30 The staff also audited the description of the Inspection of Internal Surfaces in Miscellaneous Piping and Ducting Components AMP provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.25, Lubricating Oil Analysis Summary of Information in the Application. The SLRA states that AMP B.2.1.25, Lubricating Oil Analysis, is an existing program that will be consistent with the program elements in GALL-SLR Report AMP XI.M39, Lubricating Oil Analysis.
Audit Activities. During its audit, the staff reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal. The table below lists the documents that were reviewed by the staff and were found relevant to the Lubricating Oil Analysis program. The staff will document its review of relevant OE in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M39 Program Basis Document Lubricating Oil Analysis Program Revision 1 AR-4080012-15 Dresden Lubricating Oil Monitoring 02/23/2018 AR-04400510 Elevated Boron Additive Level in Engine Oil 11/30/2021 ATI # 101522-45-28 RCMT Re-Opened per IR-10677610 to Update Programmatic Attribute Y 07/17/2014 AR-04452493 Elevated Water Levels Verified in 28 RWCU Oil Sample 11/12/2021 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
The staff also audited the description of the SLRA AMP Lubricating Oil Analysis program provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.26, Monitoring of Neutron-Absorbing Materials Other Than Boraflex Summary of Information in the Application. The SLRA, as modified by letter dated February 20, 2025 (ML25051A253), states that AMP B.2.1.26, Monitoring of Neutron-Absorbing Materials Other than Boraflex, is an existing program with one enhancement that will be consistent with the program elements in GALL--SLR Report AMP XI.M40, Monitoring of Neutron-Absorbing Materials Other than Boraflex. To verify this claim of consistency, the staff audited the SLRA AMP.
31 Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M40 Monitoring of Neutron-Absorbing-Materials Other Than Boraflex Revision 1 NF-AA-610 Constellation Proprietary. On-Site Wet Storage of Spent Nuclear Fuel Revision 19 AR 01564488 Aging Management Program Review of Boral Spent Fuel Racks 09/27/2013 DTS 0800-01 High Density Spent Fuel Storage Rack Surveillance (W-1) (W-9)
Revision 12 WO 19880201 Boral Coupon Examination Results For CE-D-07 and CE-D-08, DTS 0800-01, SP 87-9-141, Unit 3 02/01/1988 WO 19820219 Boral Coupon Examination Results For CE-D-01 and CE-D-02, DTS 0800-01, Unit 3 02/19/1982 WO 19950808 Boral Coupon Examination Results For CE-D-11 and CE-D-12, DTS 0800-01, Unit 2(3) 08/08/1995 WO 20020614 Boral Coupon Examination Results For CE-D-13 and CE-D-14, DTS 0800-01, Unit (3) 06/14/2002 WO 01386610 00010900-02, COM, D3 10Y COM REG Boral Coupon Report, W; D03Z0800TSNRMDR01S 04/12/2012 WO 01531422 00010900-02, COM, D3 10Y COM REG Boral Coupon Report, W; D03Z0800TSNRMDR01S 05/30/2023 EC 642308 Use of Unit 3 Boral Coupons for HDFR Corrosion Surveillance Program Revision 0 N/A UFSAR Change Package 08/01/2024 NF-AA-600 Constellation Proprietary. Spent Fuel Management Revision 9 PMMR 10900 10 Y Coupon Removal Not Specified N/A TRP 40 Enhancement #1 Additional Information Not Specified During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding elements of the GALL-SLR Report AMP after implementation of the identified enhancements.
The staff also audited the description of the SLRA Monitoring of Neutron-Absorbing Materials Other than Boraflex program provided in the UFSAR supplement, as modified by letter dated February 20, 2025 (ML25051A253). The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
32 SLRA AMP B.2.1.27, Buried and Underground Piping and Tanks Summary of Information in the Application. The SLRA states that AMP B.2.1.27, Buried and Underground Piping and Tanks, is an existing program with enhancements and an exception that will be consistent with the program elements in GALL-SLR Report AMP XI.M41, Buried and Underground Piping and Tanks. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M41 Program Basis Document Buried and Underground Piping and Tanks, GALL-SLR Program XI.M41 - Buried and Underground Piping and Tanks Revision 1 ER-AA-5400-1004 Constellation Proprietary. Cathodic Protection System Management Guide Revision 2 ER-AA-5400-1002 Constellation Proprietary. Underground Piping and Tank Examination Guide Revision 10 SA-AA-117 Constellation Proprietary. Excavation, Trenching, and Shoring Revision 25 AR 101522-34 Aging Management Program (AMP) Effectiveness Review Dresden Station AMP B1.25 (Buried Piping and Tank Inspections) 06/19/2018 AR 4356004-15 Dresden Buried Pipe Program, 2020 Self-Assessment 08/20/2021 AR 02548166 Need Rectifiers Interrupted 08/28/2015 AR 02551490 CCP: Cathodic Protection Follow-up Actions From IR 02548166 09/04/2015 AR 02733198 INPO Recommendation - Cathodic Protection 10/27/2016 K-4080 General Work Specification Maintenance/Modification Work Dresden Station - Units 2 & 3 Revision 9 WO 00899125-09 CM Apply Coating System to New HPCI Piping 10/13/2006 WO 00899125-10 CM Backfill the Trench per Engineering Direction 10/18/2006 AR 00928304 Elevated Tritium Values Identified in two Storm Drains 06/05/2009 AR 01252357 Pin Hole Leak Found in Buried Pipe 08/17/2011 AR 01253628 Pin Hole Leak in Pipe 08/20/2011 AR 03976504 U3 EDG FOST Wall Thickness Results and Remaining Life 02/21/2017 AR 04182528 Underground Fire Hdr Leak Near the New Diesel Tank 10/11/2018
33 During the audit, the staff verified the applicants claim that the scope of program program element of the SLRA AMP is consistent with the corresponding element of the GALL-SLR Report AMP. In addition, the staff found that for the preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements, sufficient information was not available to determine whether they were consistent with the corresponding program elements of the GALL-SLR Report AMP. The staff will consider issuing RAIs in order to obtain the information necessary to verify whether these program elements are consistent with the corresponding program elements of the GALL-SLR Report AMP.
During the audit, the staff made the following observation:
The staff reviewed WO 00899125-09 and WO 00899125-10 and noted that the piping was externally wrapped with (a) Tapecoat M50 RC, which has thickness of 50 +/- 2 mils; and (b) a polyethylene film, which has a nominal thickness of 8 mils.
The staff also audited the description of the SLRA Buried and Underground Piping and Tanks program provided in the UFSAR supplement. The staff found that sufficient information was not available to determine whether the description provided in the UFSAR supplement was an adequate description of the SLRA Buried and Underground Piping and Tanks program. The staff will consider issuing RAIs in order to obtain the information necessary to verify the sufficiency of the UFSAR supplement program description.
SLRA AMP B.2.1.28, Internal Coatings/Linings for In-Scope Piping, Piping Components, Heat Exchanger, and Tanks Summary of Information in the Application. The SLRA states that AMP B.2.1.28, Internal Coatings/Linings for In-Scope Piping, Piping Components, Heat Exchanger, and Tanks, is a new program that will be consistent with the program elements in GALL-SLR Report AMP XI.M42, Internal Coatings/Linings for In-Scope Piping, Piping Components, Heat Exchanger, and Tanks. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this new program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.M42 Program Basis Document--
Internal Coatings/Linings for In-Scope Piping, Piping Components, Heat Exchangers, and Tanks Revision 1 AR 02408789 NDE UT for IC Shell (Unit 3) 11/08/2014 AR 04294140 D2R26 2-1503-A, 2A LPCI HX Coating Inspection Results 11/02/2019 AR 04461094 D2R27 2B LPCI HX As-found Coating Inspection Results 11/15/2021 AR 04519439 2A TBCCW Heat Exchanger Cleaning and Inspection 08/29/2022
34 WO 01029546 D2/3 10Y COM Clean/Insp SBO Diesel Fuel Oil Storage Tank 8/21/2019 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
During the audit, the staff made the following observations:
1.
The Program Basis Document provided the following information for the internally coated drywell equipment drain sump heat exchangers and reactor building equipment drain tank heat exchangers.
There are no downstream components credited with performing 10 CFR 54.4 (a)(1), (a)(2), or (a)(3) functions that are susceptible to flow blockage from potential coating debris.
The waste water environment does not promote accelerated corrosion or microbiologically induced corrosion of these components.
There are no uncoated components in the vicinity that could cause galvanic corrosion.
2.
The Program Basis Document provided the following information for the internally coated turbine oil reservoirs.
The tanks are drained, cleaned and inspected each refueling outage.
The tank pumps have screens and filters to remove particulate, and there is instrumentation that can monitor filter differential pressure.
The lubricating oil environment does not promote accelerated corrosion or microbiologically induced corrosion of these components.
The staff also audited the description of the SLRA Internal Coatings/Linings for In-Scope Piping, Piping Components, Heat Exchanger, and Tanks program provided in the UFSAR supplement.
The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.29, ASME Section XI, Subsection IWE Summary of Information in the Application. The SLRA states that AMP B.2.1.29, ASME Section XI, Subsection IWE, is an existing program with enhancements and one exception that will be consistent with the program elements in GALL-SLR Report AMP XI.S1,ASME Section XI, Subsection IWE.. To verify this claim of consistency, the staff audited the SLRA AMP. During the audit, the staff also reviewed the exception and enhancements associated with this AMP.
35 Audit Activities. During its audit, the staff reviewed documentation contained in the SLRA and ePortal. For the OE review, the applicant also made a presentation on the process used to identify and evaluate the pertinent OE.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.S1 Dresden Nuclear Power Starion (DNPS) Subsequent License Renewal Project, Program Basis Document, ASME Section XI, Subsection IWE (GALL-SLR Program XI.S1)
Revision 1 DR-AMRBD-MEAE Subsequent License Renewal Project - Materials, Environments, and Aging Effects - Aging Management Review Basis Document Revision 1 N/A DNPS Subsequent License Renewal Operating Experience Review Process Review 09/17/2024 N/A DNPS Operating Experience Review Summary Spreadsheet -
Keyword Search Results 09/17/2024 N/A Primary Containment Aging Management Review Report Revision 1 (07/24/2023)
ER-AA-700 Constellation Proprietary. LR Implementation Program -
Procedure Revision 10 ER-AA-700-1003 Constellation Proprietary. Use of Operating Experience for License Renewal Implementation / Aging Management -
Procedure Revision 6 PI-AA-125 Constellation Proprietary. Corrective Action Program (CAP)
Procedure Revision 9 ER-AA-335-018 Constellation Proprietary. Visual Examination of ASME IWE Class MC and Metallic Liners of Class CC Components Revision 17 ER-AA-330-007 Constellation Proprietary. Visual Examination of Section XI Class MC Surfaces and Class CC Liners Revision 15 ER-DR-330-1001 Constellation Proprietary. Dresden Units 2 & 3, ISI Program Plan (ISI - Sixth Inspection Interval; CISI - Fourth Inspection Interval)
Revision 3 DOS 16--31 Unit 2 (3) Drywell Annulus Leakage Inspection Revision 05 MA-AA-736-600 Constellation Proprietary. Procedure - Torquing and Tightening of Bolted Connections Revision 14 WO 01884658 01 D2[R25] RFLCom Primary Required ISI Containment Inspections
[includes IWE Results and ARs]
12/11/2017 WO 04749274 01 D2[R26] RFLCom Primary Required ISI Containment Inspections
[includes IWE Results and ARs]
11/13/2019 WO 01791787 01/02 D3[R24] RFLCom Primary Required ISI Containment Inspections
[includes IWE Results, and ARs and Torus Project (desludging, inspection and coating)]
07/13/2016 /
11/15/2016 WO 04599410 01/02 D3[R25] RFLCom Primary Required ISI Containment Inspections
[includes IWE Results]
10/13/2018 /
12/06/2018 WO 05127484 01/02 D3[R27] RFLCom Primary Required ISI Containment Inspections
[includes IWE Results]
11/09/2022/
07/28/2022 EC 642966 D3R28 Containment Shell UT Analysis Low Spot at170 Degrees Elevation 521 Revision 0 (11/22/2024)
36 Document Title Revision / Date EC 639514 SLR Fatigue Waiver Analysis of the Dresden Drywell (Including Mechanical and Electrical Penetrations)
Revision 0 (12/04/2023)
WO 05127484 D3 RFL Com Primary Required ISI Containment inspections 01/30/2023 EC 638774 Dresden U3 Containment Shell Core Bore Hole UT Analysis (no drywell shell degradation is occurring at the sand pocket location based on 15 sets of UT inspection data at 22 DW core bore hole locations over past 34 years) [superseded EC 373104]
04/18/2023 EC 638775 Dresden U3 Containment Shell UT Analysis of Spherical and Cylindrical Locations ATI 101522.35.05 04/26/2023 EC 629967 D2R26 Engineering Evaluation for Moisture Barrier and Drywell Liner Degradation 11/11/2019 WO 04999904 01 Request D2R27 WO for DW Moisture Barrier Replacement 07/20/2021 AR 04535907 D3R27 IWE Recordable Indications DW Basement and Torus Interior 11/09/2022 AR 04295748 D2R26 U2 DW Basement Primary Containment Metallic Liner VT-1 Exam Results 11/08/2019 AR 04379976 D3R26 Drywell Basement Moisture Barrier Relevant Conditions 10/27/2020 AR 04294208 D2R26 Drywell Basement Moisture Barrier Relevant Conditions 11/03/2019 AR 04189035 Remove Debris Collection Against U3 Torus Shell 10/28/2018 AR 04198189 D3R25 Drywell Coating Assessment Report 11/28/2018 AR 04071288 Recordable Indications on Unit 2 Drywell Moisture Barrier 11/05/2017 AR 04071235 U2 Drywell to Torus Bellows Seal Leakage Identified (Drywell to Torus Bellows drain line) 11/05/2017 AR 02583636 U2 Drywell Annulus Leakage Found 11/07/2015 DR-TLAABD TLAA Basis Document - Part 2 - TLAA Evaluation Dresden LR Revision 0 (04/01/2024)
SIR-01-003 (EPRI 1002861)
Users Manual for FatiguePro Fatigue Monitoring System, Version 3.0 Revision 1 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are or will be consistent with the corresponding elements of the GALL-SLR Report AMP after implementation of the identified enhancements.
In addition, the staff found that for the parameters monitored or inspected and detection of aging effects program elements, associated with the exception and enhancements, sufficient information was not available to determine whether aspects not associated with the exception were consistent with the corresponding program elements of the GALL-SLR Report AMP. The staff will consider issuing RAIs or use a voluntary SLRA supplement to obtain the information necessary to verify whether these program elements are consistent with the corresponding program elements of the GALL-SLR Report AMP.
37 The staff also audited the AMR line items related to the ASME Section XI, Subsection IWE AMP and those associated with SLRA Section 4.6 primary containment fatigue TLAAs.
During the audit, the staff made the following observations:
The staff reviewed the preventive actions element in DR-PBD-AMP-XI.S1, Section 3.2 and noted that the applicant determined no apparent concerns for accelerated degradation of the drywell shell plates at the sand bed region due to the 34 years of UT data providing no evidence of wall thinning in the sand bed region.
The staff reviewed the detection of aging effects element in DR-PBD-AMP-XI.S1, Section 3.4 and noted the statement that augmented examinations consisting of VT-1 or volumetric examination were identified in the CISI Program Plan (22-U3 core bore hole UT locations in the sand bed region and U3 moisture barrier interface of DW with concrete floor with the moisture barrier being replaced in 2022).
The staff reviewed the monitoring and trending element in DR-PBD-AMP-XI.S1, Section 3.5 and noted that DNPS Unit 3 was chosen for augmented UT examinations using 22 drilled core bore holes because of the existence of conditions that are considered to be the most potentially corrosive of the two units, which include introduction of significant water into the drywell annulus to extinguish fires that occurred in 1986 and 1988.
The staff reviewed the program description in DR-PBD-AMP-XI.S1, Section 2.1, and noted that plant-specific OE for Units 2 and 3 has confirmed that there has been some evidence of moisture traveling down from the refueling cavity past the refueling bellows and out through the sand pocket and drywell-to-torus bellows seal drains; these are monitored and evaluated by the AMP.
The staff reviewed DR-PBD-AMP-XI.S1, Section 3.4 and procedure DOS 1600-31 and noted that it provides instructions to inspect for and quantify any leakage into the annulus (expansion gap) between the drywell and the primary containment shield wall of eight drywell-to-torus bellows seal drain pipes via four pairs of drain lines, the four drywell liner sand pocket drain lines, and the entire circumference of the drywell pedestal concrete. The staff also noted that this inspection is performed once every refueling outage with the reactor cavity flooded and that the drain lines are verified to be clear of blockage prior to the inspections.
The staff reviewed Section 6.2 Augmented Examination Areas of ER-DR-330-1001 and noted that in the first, second, and third CISI intervals, portions of the DNPS Unit 3 Drywell Shell located at the sand pocket (22 core bore holes) were identified as requiring augmented examination in accordance with IWE-1240 following Examination Category E-C, item 4.12 (Surface Area Grid Minimum Wall Thickness Locations). The staff further noted that, in the fourth (current) CISI interval, the same augmented surface areas for portions of the DNPS Unit 3 Drywell Shell located at the sand pocket required volumetric examination of 100% of the minimum wall thickness locations identified during each inspection period until the areas examined remain essentially unchanged for the next inspection period.
38 The staff reviewed EC 642966 provided in response to a breakout question and noted that drywell shell UT analysis of low spot at 170 degrees Elevation 521 that surpassed 90% nominal plate thickness; however, this very localized spot (appears less than 1 in2) is not significant enough to represent a local area (a circle of diameter 0.5sqrt(Rt) =
8.97) based on guidance in the Section N-513.3 of ASME Code 1965 edition. The evaluation concluded that the 9 x 12 grid should be re-inspected on an every refueling outage frequency to characterize and trend the metal thickness of the localized low spot and surrounding plate material.
The staff reviewed enhancement 1 in SLRA Section B.2.1.29 and associated program elements in the program basis document (PBD) DR-PBD-AMP-XI.S1, and noted that the SLRA and PBD lacked sufficient clarity and technical justification for adequacy of the proposed sample and sample size of one main steam (MS) and one feedwater (FW) drywell penetration for performing surface or enhanced visual (EVT-1) examinations to detect cracking due to cyclic loading. The staff also noted a lack of clarity regarding whether enhancement 1 also included a representative sample for monitoring cracking due to stress corrosion cracking (SCC), as indicated in SLRA Section 3.5.2.2.1.6. It was also not clear if and how the proposed sample size is consistent with the representative sample size of 20 percent of the population subject to cracking for each unit as recommended in the GALL-SLR Report (e.g., AMP XI.M32, XI. M18). The staff also noted related statements that needed justification or clarification in the SLRA justification of the exception.
The staff reviewed enhancement 2 in SLRA Section B.2.1.30 and the PBD, which notes a one-time supplemental volumetric examination of containment shell surfaces that are inaccessible from one side will be performed if triggered by plant-specific OE of measurable corrosion initiated on the inaccessible side. The staff noted a lack of clarity as to whether the triggering OE has occurred to-date in Dresden Units 2 and/or 3, the definition of the local area over which triggering degradation should occur, the timing of the supplemental volumetric examination after the triggering OE is detected, and treatment of the two units if the triggering OE were to occur in one unit.
The staff reviewed PBD Section 3.4 and noted a lack of clarity as to whether the D3 RFL COM UT Inspection of Drywell Liner (PMID 4804-01, at 22 core bore holes) and D3 RFL COM UT Inspection of Cylindrical and Upper Spherical Areas of Drywell (PMID 172686-01, at 40 locations) in PBD Table 1 will continue into the subsequent period of extended operation.
The staff audited AMR items 3.5.1-009 (cumulative fatigue damage where CLB fatigue analysis exist) and 3.5.1-027 (cracking due to cyclic loading where CLB fatigue analysis does not exist) in SLRA Table 3.5.2-9 and noted that the table lacked clarity regarding components subject to supplemental surface or EVT-1 examination, components not requiring aging management for cracking based on a new fatigue waiver analysis performed for the SLRA, and components crediting the CLB fatigue TLAA. The staff also noted a discrepancy in that there are several component types in SLRA Table 3.5.2-9 that credit both AMR items 3.5.1-027 and 3.5.1-009, which appears contradictory.
The staff will consider issuing RAIs and/or use a voluntary SLRA supplement to obtain the necessary information to address issues identified in the last four bullets above during the audit as noted above. The staff will document its review of these issues in the SE.
39 The staff also audited the description of the SLRA AMP ASME Section XI, Subsection IWE provided in the UFSAR supplement Section A.2.1.29. The staff verified that this description is consistent with the description provided in the GALL-SLR Report, noting that potential changes to the enhancements, as discussed above, may need to be made in a supplement.
SLRA AMP B.2.1.30, ASME Section XI, Subsection IWF Summary of Information in the Application. The SLRA states that AMP B.2.1.30 ASME Section XI, Subsection IWF, is an existing program with enhancements that, when implemented, will be consistent with the program elements in GALL-SLR Report AMP XI.S3, ASME Section XI, Subsection IWF.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and ePortal.
For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision/Date DR-PBD-AMP-XI.S3 DNPS Subsequent License Renewal Project, Program Basis Document, ASME Section XI, Subsection IWF (GALL-SLR Program XI.S3)
Revision 1 DR-AMRBD-MEAE Subsequent License Renewal Project - Materials, Environments, and Aging Effects - Aging Management Review Basis Document Revision 1 N/A DNPS Subsequent License Renewal Operating Experience Review Process Review 09/17/2024 N/A DNPS Operating Experience Review Summary Spreadsheet -
Keyword Search Results 09/17/2024 ER-AA-335-016 Constellation Proprietary. Procedure - VT-3 Visual Examination of Component Supports, Attachments and Interiors of Reactor Vessels Revision 14 ER-AA-330-003 Constellation Proprietary. Procedure - Inservice Inspection of Section XI Component Supports Revision 16 ER-DR-330-1001 Constellation Proprietary. ISI Program Plan - Sixth Inspection Interval (01/20/2023 to 01/19/2033), Dresden Generating Station, Units 2 & 3 Revision 3 ER-DR-330-1003 Constellation Proprietary. ISI Selection Document, Sixth Inspection Interval, Dresden Generating Station, Units 2 & 3 Revision 1 B-23 DNPS Unit 2 Containment Vessels Loading - Sections & Details 03/14/1967 B-240 DNPS Unit 2 Reactor Building Framing - Section & Details Sheet 2
Revision H B-504 DNPS Unit 3 Containment Vessels Loading - Sections & Details Revision B
40 Document Title Revision/Date B-670 DNPS Unit 3 Reactor Building Framing - Section & Details Sheet 2
Revision C WO 0160851 NDE Report 14-572 and 14-574 VT-3 Visual Examination of U3 RPV Stabilizer Support (pages 10-12 & 19-21) 11/15/2014 &
11/10/2014 WO 01899866 NDE Report 17-395 VT-3 Visual Examination of U2 RPV Skirt and 17-334/17-335 Visual of U2 RPV Stabilizer Support (pages 149-156) 11/10/2017 &
11/5/2017 WO 04997403 NDE Report D2R27-VT-029, D2R27-VT-031 Visual Examination of U2 Reactor Stabilizer Supports (pages 36 & 37) 11/11/2021 &
11/13/2021 WO 05121032 NDE Report D3R27-VT-057, D3R27-VT-052 - Visual Examination of U3 Reactor Stabilizer Supports (pages 73 & 74) 11/07/2022 WO 05236469 NDE Report D3R27-VT-056, D3R27-MT-009 - Visual VT-3 Examination of U3 RPV Support Skirt and MT of U3 Reactor Skirt Support Weld (pages 37 & 38) 11/07/2022 WO 01884658 NDE Report 18-019 Unit 2 VT-3 Visual Examination of Torus Non-Piping Supports 02/07/2018 AR 04459882 D2R27 VT-3 Support ISI Exam Improper cold setting spring can 11/10/2021 AR 04295345 D2R26 Found Loose Nut on SBLC Pipe Support During VT-3 Inspection 11/07/2019 AR 04534843 D3R27 NDE VT-3 Exam identified Recordable Indications (HPCI) 11/04/2022 AR 04535230 D3R27 M-1187-D-266 VT-3 IWF Support Indications (RWCU) 11/07/2022 AR 04713727 Moderate to heavy corrosion found on CCSW pipe support (LPCI
& CCSW) 10/30/2023 AR 04714132 D2R28 - ISI [VT-3] Exam Relevant Condition on M-1167D-1 Support (RX) (RPV, RECIRC, MSIV, ADS, INST) 10/31/2023 AR 04715010 D2R28 - ISI [VT-3] Exam Relevant Condition on M-3209-13 Pipe Support (Variable Spring) (LPCI & CCSW) 11/03/2023 AR 04715663 D2R28-5605A MS Hanger Support has concrete damage 11/06/2023 AR 04715724 D2-R28 ISI Exam Relevant Condition on M-1157D-261 Support 11/06/2023 AR 04814342 D3-R28 ISI Exam Relevant Condition on M-1190D-285 Support 11/01/2024 AR 04814350 D3-R28 ISI Exam Relevant Condition on M-1200D-96 Support 11/01/2024 AR 01588221 D2 M-1151D-294 Found Outside Cold Load Range in EC 34506711/21/2013 AR 00834825 Corrosion on Two Unit 2 Torus Support Baseplates 10/23/2008 During the audit, the staff verified the applicants claim that the preventive actions, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are or will be consistent with the corresponding elements of the GALL-LR Report AMP XI.S3 after implementation of the identified enhancements.
In addition, the staff found that for the scope of program, parameters monitored or inspected and detection of aging effects (e.g., elastomeric vibration isolation elements) program
41 elements, sufficient information was not available to determine whether they were consistent with the corresponding program elements of the GALL-SLR Report AMP as applicable to DNPS. The staff will consider issuing RAIs or use a voluntary SLRA supplement to obtain the information necessary to verify whether these program elements are consistent with the corresponding program elements of the GALL-SLR Report.
The staff also audited the AMR line items related to the ASME Section XI, Subsection IWF AMP.
During the audit, the staff made the following observations:
The staff reviewed SLRA Section B.2.1.30 and the IWF AMP PBD DR-PBD-AMP-XI.S3, and noted that there was a lack of clarity as to whether the reactor vessel support skirt to ring girder bolting pertains to: 1) only high-strength bolting in sizes greater than 1-inch nominal diameter used at DNPS, or 2) the total population of such bolting that is sampled in enhancement 5 for volumetric examination to detect cracking due to SCC.
The staff reviewed enhancement 3 in SLRA Section B.2.1.30 and noted that it did not appear to include any additional new high-strength bolting in sizes greater than 1-inch nominal diameter that may potentially be added prior to the subsequent period of extended operation for volumetric examination to detect cracking.
The staff noted from its review of the SLRA that regarding Table 3.5.1 AMR line item 3.5.1-085 and its corresponding SLRA Table 3.5.2-11 item for managing loss of material for stainless steel structural bolting in a treated water environment, sufficient information was not provided to determine the consistency of the AMR item with GALL-SLR.
Regarding the FE in SLRA Section 3.5.2.2.2.6 for the reactor vessel supports, the staff noted that, while a plant-specific AMP may not be necessary, loss of fracture toughness due to irradiation embrittlement remains an applicable new aging effect/mechanism for the RPV steel supports for SLR. The staff further noted that:
o neither the IWF PBD on the ePortal nor the SLRA itself includes loss of fracture toughness due to irradiation embrittlement among the aging effects/mechanisms managed by the program, o
SLRA Sections 3.5.2.1.2, 3.5.2.1.9, Table 3.5.2-2, and Table 3.5.2-9 do not appear to include AMR items, o
the aging effect will be managed by the IWF AMP, and o
SLRA B.2.1.30 does not appear to include loss of fracture toughness due to irradiation embrittlement as an aging effect that will be managed by the program.
The staff will consider issuing RAIs or use a voluntary SLRA supplement to obtain the information necessary to make its finding regarding the issues in the observations above.
The staff also audited the description of the SLRA AMP ASME Section XI, Subsection IWF provided in UFSAR supplement Section A.2.1.30. The staff found that sufficient information was not available to determine whether the description provided in the UFSAR supplement was an adequate description of the SLRA AMP ASME Section XI, Subsection IWF. The staff will consider issuing an RAI or use a voluntary SLRA supplement to obtain the information necessary to verify the sufficiency of the UFSAR supplement program description.
42 SLRA AMP B.2.1.31, 10 CFR Part 50, Appendix J Summary of Information in the Application. The SLRA states that AMP B.2.1.31, 10 CFR Part 50, Appendix J, is an existing program that is consistent with the program elements in GALL-SLR Report AMP XI.S4, 10 CFR Part 50, Appendix J.
Audit Activities. The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.S4 Dresden Nuclear Power Station Program Basis Document Rev. 1 AR 2584095 Dresden Generating Station, Action Request Excessive Leakage Through Relief Valve 2-8526 During LLRT 11/08/2015 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLRReport AMP.
The staff also audited the description of the SLRA 10 CFR Part 50, Appendix J AMP provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the SRP-SLR.
SLRA AMP B.2.1.32, Masonry Walls Summary of Information in the Application. The SLRA states that AMP B2.1.32, Masonry Walls, is an existing program that is consistent with the program elements in GALL-SLR Report AMP XI.S5, Masonry Walls. To verify this claim of consistency, the staff audited the SLRA AMP. The staff will address issues identified but not resolved in this audit report in the SE.
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.S5 Program Basis Document Masonry Walls GALL-SLR Program XI.S5 - Masonry Walls Revision 1 AR 02695899 Action Request: Cracks Observed in Fire Walls 142 and 143, U2 Turbine Building 07/22/2016 WO 01463277 Work Order:D2/3 5Y COM D2&D3 Crib House El 490-8, 509-6 06/27/2016 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
43 The staff also audited the description of the SLRA Masonry Walls program provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.33, Structures Monitoring Summary of Information in the Application. The SLRA states that AMP B.2.1.33, Structures Monitoring, is an existing condition monitoring program with enhancements that will be consistent with the program elements in GALL-SLR Report AMP XI.S6, Structures Monitoring.
Audit Activities. In addition to the OE documentation contained in the SLRA and ePortal, the staff observed the applicants search of its operating experience database using the keywords.
An onsite audit was performed from December 10, 2024, to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.S6 Dresden Nuclear Power Station Subsequent License Renewal Project, Program Basis Document, Structures Monitoring Revision 02 AD-AA-101-1010 Constellation Proprietary. Exelon Generation Standard Numbering Convention Revision 12 SLR-DRE-B-01A, SLR-DRE-Index, and SLR-DRE-M-1A License Renewal Drawing Composite Site Plan Revision 0 ER-AA-450 Constellation Proprietary. Constellation Fleet Plant Procedure, Structures Monitoring Revision 11 ER-DR-450-1001 Constellation Proprietary. Dresden Structures Monitoring Instructions Revision 0 MA-AA-736-600 Constellation Proprietary. Constellation Plant Fleet Procedure, Torquing and Tightening of Bolted Connections Revision 15 PES-S-010 Constellation Proprietary. Exelon Nuclear Generation Group Procurement Engineering Standards, Fasteners Revision 05 ER-AA-700 Constellation Proprietary. Constellation Plant Fleet Procedure, License Renewal Implementation Program Revision 10 AR 01297234 NRC Information Notice (IN) 2011-20 Concrete Degradation by Alkali-Silica Reaction 12/02/2011 AR 02407382 Safety: Low Pressure (LP) Heater Bay Significant Steel Corrosion at 502 Elevation 11/05/2014 AR 02682165 Unit 3 Reactor Building - Roof Leaks in Southwest Quadrant 06/16/2016 AR 014143026 Unit 2 Torus Basement Bay 7 Reactor Building Equipment Drain Tank (RBEDT) Room Elevation 496 Access Gallery - Degraded Support on the Concrete Wall 05/31/2018 AR 04146462 Unit 2 Torus Basement Water In-Leakage Causing Support Degradation 06/12/2018 EC 0000624174 Analysis of Low Pressure Coolant Injection (LPCI) System Drain Line 2-1542A-1.5/2-L With and Without Supports 12/21/2018
44 Document Title Revision / Date EC 000062913 Degraded Structural Steel Support Beams 08/16/2020 WO 04853954 Degraded Structural Steel Near W. Water Box Access Door 08/17/2020 IR 2558847 Concrete Needs Repair: Pieces Are Loose & Falling to Ground on the Outside of Reactor Building Drawing No. B-27 Dresden Units 2 and 3, Concrete Elevation Chimney Elevations and Plans Revision H Drawing No. B-28 Dresden Units 2 and 3, Concrete Ventilation Chimney Sections
& Details 06/09/1967 Drawing No. B-1177 Dresden Units 2 and 3, Stack & Chimney Inspection 01/15/1975 UFSAR ML23180A022 Dresden - UFSAR, Chapter 3, Design of Structures, Components, Equipment, and Systems Revision 15 WO 01512813 WO 01601817 WO 01698314 WO 01793913 WO 01888740 WO 04580569 WO 04867735 WO 05429441 Dresden Units 1 to 3 Communication Microwave Tower &
Chimney Paint Inspection 12/12/2012 10/30/2013 12/10/2014 11/02/2015 12/08/2016 12/08/2017 01/02/2020 12/19/2024 AR 02396030 Large Calcium Deposit on Conduit in Cable Tunnel 10/15/2014 AR 01766696 Cable Conduit Above 2B Circulating Pump In-Ground Leak 11/17/2014 AR 02497196 Units 2 and 3 Crib House In-Leakage Source Identified 06/06/2015 AR 04149799 Units 2 and 3 Crib House Cable Tray Rusting Out 07/23/2018 AR 02682457 Units 2 and 3 Crib House Building - Roof Degradation 07/16/2016 AR 04425521 Debris and Vegetation to Be Removed from Station Blackout (SBO) Roof Structure 06/24/2021 AR 04426959 North Turbine Building Roof Deterioration 07/01/2021 AR 04468420 Water Leak Turbine Building Roof 01/26/2022 Technical Evaluation EC 643515 Dresden Units 2 and 3, Concrete Temperature Evaluation at Main Steam Line Penetrations Revision 0 Drawing No. M-97 Dresden Units 2 and 3, Reactor Building Piping Drywell Penetration Details Revision AA Drawing No. B-440 Dresden Units 1, 2, and 3, Typical Details for Sealing Floor &
Wall Openings, Sheet 1 Revision C During the audit, the staff verified the applicants claim that the corrective actions program element of the SLRA AMP is consistent with the corresponding element of the GALL-SLR Report AMP. In addition, the staff found that for the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, and acceptance criteria program elements, sufficient information was not available
45 to determine whether they were consistent with the corresponding program elements of the GALL-SLR Report AMP. The staff will consider issuing RAIs in order to obtain the information necessary to verify whether these program elements are consistent with the corresponding program elements of the GALL-SLR Report AMP.
During the audit, the staff made the following observations:
For the scope of program program element, the staff noted that transformer TR 86 is within the scope of subsequent license renewal; however, it was not included in the SLRA.
For the Preventive Actions program element, the staff noted that the existing AMP does not address preventive actions such as the proper selection of bolting material and lubricants, or the application of appropriate installation torque or tension to prevent or minimize loss of bolting preload and cracking of high-strength bolting.
For the parameters monitored or inspected program element, the staff noted that Enhancement 6 does not identify aging mechanisms associated with increased porosity and permeability of concrete.
For the Monitoring and Trending program element, the staff noted that Enhancement 13 lacks acceptance criteria for the quantitative baseline inspection, as described in the GALL-SLR Report.
For the detection of aging effects program element, the staff noted that the existing AMP does not include procedures for detecting cracking due to expansion from reaction with aggregates.
For the detection of aging effects program element, the staff observed several instances of water leakage that led to degradation of structural steel components and required engineering evaluations. These findings suggest that the AMP may need to include provisions for more frequent inspections based on the extent of the observed degradation.
During the onsite audit, the staff performed walkdowns of the Reactor Building, Turbine Building, Crib Houses, Control Building Structures, Chimneys and Yard Structures. The staff made the following observations during walkdowns:
During the walkdown of the Unit 1 Crib House, the staff found the structure to be in good condition.
During the walkdown of the Units 2 and 3 Crib House, the staff noted the following conditions:
o Significant corrosion of the south side lower cable tray and its supports, running between the 2A and 2B circulating water pumps, attributed to periodic water intrusion from electrical penetrations (ductbanks) located above the tray.
o A steel support column with a baseplate using only three bolts.
46 o
Dark discoloration observed on the walls in the fish and leaf removal area.
o Multiple cracks on the exterior faces of masonry walls, including diagonal cracks at some locations.
During the walkdown of the Units 2 and 3 chimney, the staff observed significant efflorescence (white and black) and minor spalling on the exterior surface of the chimney, extending from the base to approximately 25 feet elevation below the vent stack.
During the walkdown of the Units 2 and 3 Turbine Building, the staff observed significant damage and vegetation growth on portions of the Turbine Building roof, which could eventually lead to water intrusion and roof leakage.
The staff also audited the description of the SLRA Structures Monitoring program provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.34, Inspection of Water-Control Structures Associated with Nuclear Power Plants Summary of Information in the Application. The SLRA states that AMP B.2.1.34, Inspection of Water-Control Structures Associated with Nuclear Power Plants, is an existing program with enhancements and exceptions that will be consistent with the program elements in GALL-SLR Report AMP XI.S7, Inspection of Water-Control Structures Associated with Nuclear Power Plants.
Audit Activities. An on-site audit was performed December 9, 2024, to December 13, 2024, in Morris, IL to gain a general overview of current conditions of the structures compared to the provided operating experience. While onsite, the staff engaged with the applicant staff, conducted walkdowns, and reviewed documents provided by the applicant.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.S7 Program Basis Document Inspection of Water-Control Structures Associated with Nuclear Power Plants Rev. 1 WO 01434881 Dresden Units 2/3 5 Year Complete Unit 2/3 Crib House Roofs, Elev 529-0 & 540-0 06/29/2011 WO 01434907 Dresden Units 2/3 5 Year Complete D2 & D3 Crib House, Elev 490-8, 509-6, & 514-0 07/08/2011 WO 01451951 Dresden Units 2/3 5 Year Complete Unit 2/3 Crib House Roofs, Elev 529-0 & 540-0 06/16/2016 AR 000999776 LR: Evaluation of U2/3 Discharge Struct from Divers Video 12/1/2009 WO 01935132 Dresden Units 2/3 5 Year Complete Unit 2/3 Crib House Roofs, Elev 529-0 & 540-0 06/07/2021
47 WO01945594 Dresden Units 2/3 Complete D2 & D3 Crib House 07/22/2021 AR 02704605 NRC: Inspector Identified Issues 08/15/2016 AR 04035816 Water Leak Southwest Side of Crib House 07/26/2017 AR 04393484 Excessive In-Leakage onto 3C Circ Pump MOV 01/02/2021 AR 04400278 Degraded Pipe Support 02/04/2021 DTS 3900-07 Crib House/Intake Structures Inspections Rev. 14 DTS 4450-04 Dresden Credited Ultimate Heat Sink Bathymetric Surveillance for Intake and Discharge Canals Rev. 02 ER-AA-450 Constellation Proprietary. Constellation - Structures Monitoring Rev. 11 CC-AA-309-101 Constellation Proprietary. ExelonGeneration - Engineering Technical Evaluations Rev. 16 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP or will be consistent after implementation of the identified enhancements.
During the audit, the staff made the following observations:
There is a history of water leaking into the Units 2 and 3 Crib House at the conduit penetrations into the building. This water leakage into the Crib House has been documented as early as 2008, and no reports on addressing the leakage or mitigating impacts have been identified. See the TRP 046 Audit report for additional on-site audit observations on the Units 2 and 3 Crib House.
For the Scope of the Program element, the staff noted the following:
o The in-scope structures: discharge headworks and Units 2 and 3 Crib House forebay are not described in the description of the program.
o SLRA Table 2.4-4, Crib Houses is missing the in-scope Unit 1 concrete foundation For the Preventive Actions program element, the staff noted enhancement 3 describes structural bolting fabricated from ASTM A325 and ASTM A490, however, the program basis document stated that this structural bolting was not used.
For the Detection of Aging Effects program element, the staff noted that the program description to visually inspect submerged structural components in the discharge outfall every 10 years is inconsistent with GALL-SLR report.
For the Acceptance Criteria program element, the staff noted that cracked bolt are not acceptable unless accepted by engineering evaluations is not consistent with GALL-SLR report.
During the on-site audit, the staff noted a column base plate is missing one corner bolt, and the water pump support base plate anchor bolt edge clearance appears non code compliant. The staff reviewed engineering evaluations for the column and construction drawings for the water-pump and verified the conditions were satisfactorily evaluated or constructed per design.
48 The staff also audited the description of the SLRA Inspection of Water-Control Structures Associated with Nuclear Power Plants AMP provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.35, Protective Coating Monitoring and Maintenance Summary of Information in the Application. The SLRA states that AMP B.2.1.35, Protective Coating Monitoring and Maintenance, is an existing program that is consistent with NUREG-2191,Section XI.S8, Protective Coating Monitoring and Maintenance as modified by SLR-ISG-Structures-2021-03-STRUCTURES, Updated Aging Management Criteria for Structures Portions of the Subsequent License Renewal Guidance. To verify this claim of consistency, the staff audited the SLRA AMP.
Audit Activities. The table below lists the documents that were reviewed by the staff and were found to be relevant to the Protective Coating Monitoring and Maintenance Program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.S8 Program Basis Document Protective Coating Monitoring and Maintenance Revision 1 AR 04080012-10 Dresden Aging Management Program Effectiveness Review for A.1.32 - Protective Coating Monitoring and Maintenance Prog 10/10/18 AR 04381773 D3R26 Torus Underwater Unqualified Coatings Repairs Torus 11/02/20 AR 04462260 D2R27 Drywell Protective Coating Inspection Results 11/20/21 EC 632846 D3R26 Coating Eval D3R26 Containment Coating Evaluation Report for Trending and Analyzing Unit 3 Coating Failures Rev 0 EC 635542 D2R27 Coating Eval D2R27 Containment Coating Evaluation Report for Trending and Analyzing Unit 2 Coating Failures Rev 0 EC 637898 D3R27 Coating Eval D3R27 Containment Coating Evaluation Report for Trending and Analyzing Unit 3 Coating Failures Rev 1 WO 04887071 00011970-01, D3 RFL COM Desludge Torus & Inspect Coating 8/18/20 WO 04997364 00001610-02, TS, D2 RFL TS/COM Insp Torus, DW and DW Head Internal Coating 11/3/21 WO 04999904 Request D2R27 WO for DW Moisture Barrier Replacement 7/20/21 WO 05017641 00011967-01, COM, D2 RFL COM Desludge Torus & Inspect Coating 7/6/21 WO 05119688 00011970-01. COM, D3 RFL COM Desludge Torus & Inspect Coating 6/1/22 WO 05184894 D3R26 Torus Underwater Unqualified Coating Repairs 1/30/23 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and
49 trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP. During the audit of the operating experience program element, the staff reviewed a search of results of the plant-specific database to identify any previously unknown or recurring aging effects. The staff will evaluate any identified plant-specific OE in the SE.
The staff also audited the description of the SLRA AMP Protective Coating Monitoring and Maintenance program provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.36, Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Summary of Information in the Application. The SLRA notes that AMP B.2.1.36, Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements, is an existing program with enhancements that will be consistent with the program elements in GALL-SLR Report AMP XI.E1, Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the applicants basis document, available procedures, and referenced documents.
Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.E1 Program Basis Document - Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Revision 1 WO 01277120 DEE/EM Perform ALE Cable Insp.
11/17/2009 WO 01280277 DEE/EM Visual Inspect U3 Cable Termination Boxes 11/05/2010 AR 00977284 NRC Identifies Potential Finding with LR Cable Inspections 12/10/2009 AR 00979900 NRC Identifies Potential Finding with LR Cable Inspections 10/22/2009 AR 04422420 2B Reactor Recirc Pump Trip 03/10/2022 AR 04080012-12 Aging Management Program (AMP) Effectiveness Review Dresden B.1.33 Electric Cables and Connections Not Subject to EQ Revision 1 MA-AA-723-500 Constellation Proprietary. Inspection of Non EQ Cables and Connections for Managing Adverse Localized Environments Revision 13 ER-AA-300-150 Constellation Proprietary. Cable Condition Monitoring Program Revision 8
50 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding elements of the GALL-SLR Report AMP after implementation of the identified enhancements.
During the audit, the staff made the following observations:
During its review of DNPSs SLRA AMP B.2.1.36, the staff identified that the program description of the AMP was not consistent with the corresponding element in GALL-SLRReport AMP XI.E1. Specifically, the program description element for AMP B.2.1.36 did not include how the adverse localized environments (ALEs) will be identified at DNPS and the component sampling process for cable and connection electrical insulation testing. In response to staffs breakout questions, the applicant stated that the program description of SLRA AMP B.2.1.36 will be revised for consistency with GALL-SLRReport AMP XI.E1 in a future supplement. The staff verified that the applicant included the requested information in the program description of AMP B.2.1.36 in SLRA Supplement 1 (ML25051A253).
During its review of DR-PBD-AMP-XI.E1, Program Basis Document, Revision 1, the staff identified that the programs parameters monitored or inspected element and Detection of Aging Effects element were not consistent with the corresponding program elements in GALL-SLRReport AMP XI.E1. Specifically, the parameters monitored or inspected program element in DR-PBD-AMP-XI.E1, Revision 1, did not include the limit for a moisture environment and inspection for ALEs for each of the most limiting cable and connection electrical insulation plant environments (e.g., caused by temperature, radiation, moisture, or contamination); and the detection of aging effects program element in DR-PBD-AMP-XI.E1, Revision 1, did not include the evaluation of cable and connection insulation to confirm that the dispositioned corrective actions continue to support in-scope cable and connection intended functions during the subsequent period of extended operation. In response to staffs breakout questions, the applicant stated that the parameters monitored or inspected program element and the detection of aging effects program element in DR-PBD-AMP-XI.E1, Revision 1, will be revised for consistency with GALL-SLRReport AMP XI.E1.The staff also audited the description of the SLRA Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
The staff made the following observation during walkdowns:
During the onsite audit, the staff performed a walkdown of various in-scope electrical cables and connections. The staff did not observe any signs of adverse or abnormal age-related degradation with in-scope electrical insulation for electrical cables and connections not subject to 10 CFR 50.49 environmental qualification requirements.
51 SLRA AMP B.2.1.37, Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Used in Instrumentation Circuits Summary of Information in the Application. The SLRA notes that AMP B.2.1.3.37, Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Used in Instrumentation Circuits, is an existing program that is consistent with the program elements in GALL-SLR Report AMP XI.E2, Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Used in Instrumentation Circuits.
Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.E2 Program Basis Document - Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Used in Instrumentation Circuits Revision 1 AR 04080012-12 Aging Management Program (AMP) Effectiveness Review Dresden B.1.37 Electric Cables Not Subject to EQ Used in Instrument Circuits Revision 1 AR 04699193 DRE SLR: Instrumentation Cable AMP Implementation Deficiency08/02/2024 ER-AA-300-150 Constellation Proprietary. Cable Condition Monitoring Program Revision 8 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
The staff also audited the description of the SLRA Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Used in Instrumentation Circuits provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.38, Electrical Insulation for Inaccessible Medium-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Summary of Information in the Application. The SLRA notes that AMPB.2.1.38, Electrical Insulation for Inaccessible Medium-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements, is an existing program with enhancements that will be consistent with the program elements in GALL-SLRReport AMPXI.E3A, Electrical Insulation for Inaccessible Medium-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements, as modified by SLR-ISG-2021-04-ELECTRICAL, Updated Aging Management Criteria for Electrical Portions of Subsequent License Renewal Guidance. At the time of the audit, the applicant had not yet fully developed the documents
52 necessary to implement this enhanced program, and the staffs audit addressed only the applicants basis document, available procedures, and referenced documents.
Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.E3A Program Basis Document - Electrical Insulation for Inaccessible Medium-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Revision 1 NA Electrical Commodities Aging Management Review Report Part of: Electrical Components Grouping Revision 1 ER-AA-300-150 Constellation Proprietary. Cable Condition Monitoring Program Revision 8 AR 04011696 SBO Cable Vault (SBO MH-1) High Water Level 07/14/2018 AR 04823380 NRC ID: SBO MH-1 Cable Trays unable to be visually inspected 12/12/2024 WO 05052680 01 IM D2/3 18M PM Replace Manhole LT Batteries 2/3-SWYMH3-0001 03/02/2022 AR 04825192 NRC ID: SBO-MH1 Cover Condition 12/20/2025 AR 02704605 NRC Inspector Identified Issues 09/01/2016 AR 04315469 OIO Informal Benchmark from EPRI Cable Management Conference 04/15/2020 NA SBO-MH-1 (11).jpg Print date: 12/18/2025 NA SBO-MH-1 (5).jpg Print date: 12/18/2025 NA Cribhouse (1).jpg Print date: 12/18/2025 NA Cribhouse (10).jpg Print date: 12/18/2025 Action Tracking Number:
04310631 Fleet Cable Program Check In 03/31/2021 NA Breakout Question Response for Item 53.1-1 (TRP-53.1, 53.2, 53.3)
Print date: 01/21/2025 NA Breakout Question Response for Item 53.1-2 (TRP-53.1, 53.2, 53.3)
Print date: 01/21/2025 NA Breakout Question Response for Item 53.1-3 (TRP-53.1, 53.2, 53.3)
Print date: 01/21/2025 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP
53 will be consistent with the corresponding elements of the GALL-SLR Report AMP, as modified by SLR-ISG-2021-04-ELECTRICAL, after implementation of the identified enhancements.
The staff also audited the description of the SLRA Electrical Insulation for Inaccessible Medium-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report, as modified by SLR-ISG-2021-04-ELECTRICAL.
The staff made the following observations during walkdowns:
During the onsite audit, the staff interviewed the applicants staff and performed walkdowns of the DNPS. Specifically, the staff conducted onsite walkdowns of a sample of in-scope electrical manholes around the site and examined medium-voltage power cables within the electrical manholes. The staff also examined pictures of the interior of an electrical manhole that was in the scope of SLR. While the staff observed evidence of varying levels of prior wetting of in-scope manholes, the visible condition of accessible portions of in-scope cables within the manholes showed no signs of abnormal degradation.
Visual examination inside SBO MH-1 revealed a covered tray which prevented observation of any cable inside or if residual water could be trapped inside. The lack of the ability to internally inspect the covered tray was documented in a condition report; however, the licensee determined that cable inside this tray was not in-scope of SLR.
The staff also observed that the cover of SBO MH-1 was significantly corroded and at a low level compared to surrounding pavement allowing for significant pooling of stormwater and in-leakage to the manhole. The applicant generated a condition report (AR 04825192) to address this issue.
During a walkdown of the Service Water Pump room (Cribhouse), NRC staff observed signs that water leakage from the service water duct bank has been collecting in cable trays in the service water pump room potentially submerging in-scope cables. The staff requested that the applicant provide any issue reports that had been written to address this condition. The applicant informed the staff that condition report AR 2704605 had been written for this concern. In addition, these cables are tested as part of first LR and testing continues under SLR.
As part of the discussion during the walkdown, the applicants staff mentioned and physically identified that remote level monitoring was installed in three manholes to monitor water level so that dewatering activities could be performed as needed to prevent submergence of in-scope cables. NRC staff submitted a question concerning ongoing maintenance of the level monitoring systems. The applicant responded noting that battery replacement was completed on a scheduled interval and that the function of the level monitoring systems was verified each time.
SLRA AMP B.2.1.39, Electrical Insulation for Inaccessible Instrument and Control Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Summary of Information in the Application. The SLRA notes that AMPB.2.1.39, Electrical Insulation for Inaccessible Instrument and Control Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements, is a new program that will be consistent with the
54 program elements in GALL-SLRReport AMPXI.E3B, Electrical Insulation for Inaccessible Instrument and Control Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements, as modified by SLR-ISG-2021-04-ELECTRICAL, Updated Aging Management Criteria for Electrical Portions of Subsequent License Renewal Guidance. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this new program, and the staffs audit addressed only the applicants basis document, available procedures, and referenced documents.
Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.E3B Program Basis Document - Electrical Insulation for Inaccessible Instrument and Control Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Revision 1 NA Electrical Commodities Aging Management Review Report Part of: Electrical Components Grouping Revision 1 ER-AA-300-150 Constellation Proprietary. Cable Condition Monitoring Program Revision 8 AR 04329319 Inspect and Dewater Security MH1 and Switchyard MH3 04/23/2020 AR 04823380 NRC ID: SBO MH-1 Cable Trays unable to be visually inspected 12/17/2024 AR 04825192 NRC ID: SBO-MH1 Cover Condition 01/08/2025 Action Tracking Number:
04310631 Fleet Cable Program Check In 03/31/2021 NA SBO-MH-1 (11).jpg Print date: 12/18/2025 NA SBO-MH-1 (5).jpg Print date: 12/18/2025 N/A Breakout Question Response for Item 53.1-1 (TRP-53.1, 53.2, 53.3)
Print date: 01/21/2025 N/A Breakout Question Response for Item 53.1-3 (TRP-53.1, 53.2, 53.3)
Print date: 01/21/2025 WO 05052680 01 IM D2/3 18M PM Replace Manhole LT Batteries 2/3 SWYMH3-0001 03/02/2022 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP, as modified by SLR-ISG-2021-04-ELECTRICAL.
55 During the audit, the staff made the following observation:
The staff identified that Program Basis Document DR-PBD-AMP-XI.E3B was not fully consistent with GALL-SLR, as modified by SLR-ISG-2021-04-ELECTRICAL.
Specifically, DR-PBD-AMP-XI.E3B did not include the word potentially in front of exposed to significant moisture in the scope of program program element evaluation and the term age degradation was used instead of age-related degradation in the Parameters Monitored or Inspection program element evaluation. As documented in License Renewal Change Request LR-AA-1712, Rev. 000, the applicant plans to update DR-PBD-AMP-XI.E3B to make these evaluations fully consistent with GALL-SLR, as modified by SLR-ISG-2021-04-ELECTRICAL.
The staff also audited the description of the SLRA Electrical Insulation for Inaccessible Instrument and Control Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report, as modified by SLR-ISG-2021-04-ELECTRICAL.
The staff made the following observations during walkdowns:
During the onsite audit, the staff interviewed the applicants staff and performed walkdowns of the DNPS. Specifically, the staff conducted onsite walkdowns of a sample of electrical manholes around the site and examined instrumentation cables within the electrical manholes. The staff also examined pictures of the interior of an electrical manhole that was in the scope of SLR. While the staff observed evidence of varying levels of prior wetting of in-scope manholes, the visible condition of accessible portions of in-scope cables within the manholes showed no signs of abnormal degradation.
Visual examination inside SBO MH-1 revealed a covered tray which prevented observation of any cable inside or if residual water could be trapped inside. The lack of the ability to internally inspect the covered tray was documented in a condition report; however, the applicant determined that cable inside this tray was not in-scope of SLR.
The staff also observed that the cover of SBO MH-1 was significantly corroded and at a low level compared to surrounding pavement allowing for significant pooling of stormwater and in-leakage to the manhole. The applicant generated a condition report (AR 04825192) to address this issue.
As part of the discussion during the walkdown, the staff observed that remote level monitoring was installed in three manholes to monitor water level so that dewatering activities could be performed as needed to prevent cable submergence. NRC staff submitted a question concerning ongoing maintenance of the level monitoring systems in terms of assurance of continued functionality. In its response, the applicant noted that functional verification of the remote level monitoring systems, including battery replacements, were completed on scheduled intervals.
SLRA AMP B.2.1.40, Electrical Insulation for Inaccessible Low-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Summary of Information in the Application. The SLRA notes that AMPB.2.1.40, Electrical Insulation for Inaccessible Low-Voltage Power Cables Not Subject to 10 CFR 50.49
56 Environmental Qualification Requirements, is a new program with an exception that will be consistent with the program elements in GALL-SLRReport AMPXI.E3C, Electrical Insulation for Inaccessible Low-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements, as modified by SLR-ISG-2021-04-ELECTRICAL, Updated Aging Management Criteria for Electrical Portions of Subsequent License Renewal Guidance. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this new program, and the staffs audit addressed only the applicants basis document, available procedures, and referenced documents.
Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.E3C Program Basis Document - Electrical Insulation for Inaccessible Low-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Revision 1 NA Electrical Commodities Aging Management Review Report Part of: Electrical Components Grouping Revision 1 ER-AA-300-150 Constellation Proprietary. Cable Condition Monitoring Program Revision 8 AR 04011696 SBO Cable Vault (SBO MH-1) High Water Level 07/14/2018 AR 04823380 NRC ID: SBO MH-1 Cable Trays unable to be visually inspected 12/12/2024 WO 05052680 01 IM D2/3 18M PM Replace Manhole LT Batteries 2/3-SWYMH3-0001 03/02/2022 AR 04825192 NRC ID: SBO-MH1 Cover Condition 12/20/2025 AR 04315469 OIO Informal Benchmark from EPRI Cable Management Conference 04/15/2020 NA SBO-MH-1 (11).jpg Print date: 12/18/2025 NA SBO-MH-1 (5).jpg Print date: 12/18/2025 NA Breakout Question Response for Item 53.1-1 (TRP-53.1, 53.2, 53.3)
Print date: 01/21/2025 NA Breakout Question Response for Item 53.1-3 (TRP-53.1, 53.2, 53.3)
Print date: 01/21/2025 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding elements of the GALL-SLR Report AMP, as modified by SLR-ISG-2021-04-ELECTRICAL.
57 The staff also verified the applicants claim that aspects of the corrective actions program element not associated with the exception identified in the SLRA or by the staff during the audit are consistent with the corresponding program elements inthe GALL-SLR Report AMP.
During the audit, the staff made the following observation:
During the audit, the staff identified that Program Basis Document DR-PBD-AMP-XI.E3C was not fully consistent with GALL-SLR, as modified by SLR-ISG-2021 ELECTRICAL. Specifically, DR-PBD-AMP-XI.E3C did not include the word potentially in front of exposed to significant moisture in the scope of program program element evaluation and the term age degradation was used instead of age-related degradation in the Parameters Monitored or Inspection program element evaluation. As documented in License Renewal Change Request LR-AA-1712, Rev. 000, the applicant plans to update DR-PBD-AMP-XI.E3C to make these evaluations fully consistent with GALL-SLR, as modified by SLR-ISG-2021-04-ELECTRICAL.
The staff also audited the description of the SLRA Electrical Insulation for Inaccessible Low-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report, as modified by SLR-ISG-2021-04-ELECTRICAL.
The staff made the following observations during walkdowns:
During the onsite audit, the staff interviewed the applicants staff and performed walkdowns of the DNPS. Specifically, the staff conducted onsite walkdowns of a sample of in-scope electrical manholes around the site and examined low-voltage power cables within the electrical manholes. The staff also examined pictures of the interior of an electrical manhole that was in the scope of SLR. While the staff observed evidence of varying levels of prior wetting of in-scope manholes, the visible condition of accessible portions of in-scope cables within the manholes showed no signs of abnormal degradation.
Visual examination inside SBO MH-1 revealed a covered tray which prevented observation of any cable inside or if residual water could be trapped inside. The lack of the ability to internally inspect the covered tray was documented in a condition report; however, the applicant determined that cable inside this tray was not in-scope of SLR.
The staff also observed that the cover of SBO MH-1 was significantly corroded and at a low level compared to surrounding pavement allowing for significant pooling of stormwater and in-leakage to the manhole. The applicant generated a condition report (AR 04825192) to address this issue.
As part of the discussion during the walkdown, the staff observed that remote level monitoring was installed in three manholes to monitor water level so that dewatering activities could be performed as needed to prevent cable submergence. NRC staff submitted a question concerning ongoing maintenance of the level monitoring systems in terms of assurance of continued functionality. In its response, the applicant noted that functional verification of the remote level monitoring systems, including battery replacements, were completed on scheduled intervals.
58 SLRA AMP B.2.1.41, Metal Enclosed Bus Summary of Information in the Application. The SLRA notes that AMP B.2.1.41, Metal Enclosed Bus, is an existing program with enhancement that will be consistent with the program elements in GALL-SLR Report AMP XI.E4, Metal Enclosed Bus. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the applicants basis document and referenced documents.
Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.E4 Program Basis Document GALL-SLR Program XI.E4 -
Metal Enclosed Bus Revision 1 AR 0480012-13-01 Aging Management Program (AMP) Effectiveness Review Dresden AMP A.2.2 Revision 1 AR 04155308 2/3 EDG Non seg bus EMI test result recommendations 02/26/2019 AR 04192407 EMI Test Results for U3 EDG Non-Seg Bus 11/08/2018 AR 04275516 EMI Test Results for TR-22 to Busses 23/24 09/03/2019 AR 04471218 EMI Test Results for NSB for U2 EDG 02/15/2022 AR 04471219 EMI Test Results for NSBs from RAT 32 to Bus 33/34 02/24/2022 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP will be consistent with the corresponding elements of the GALL-SLR Report AMP after implementation of the identified enhancements.
The staff also audited the description of the SLRA Metal Enclosed Bus provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.2.1.42, Electrical Cable Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Summary of Information in the Application. The SLRA notes that AMP B.2.1.42, Electrical Cable Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements, is a new program that will be consistent with the program elements in GALL-SLR Report AMP XI.E6, Electrical Cable Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements. At the time of the audit, the applicant had not yet fully developed the documents
59 necessary to implement this new program, and the staffs audit addressed only the applicants basis documents and referenced documents.
Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-XI.E6 Program Basis Document - Electrical Cable Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Revision 1 ER-AA-700-1003 Constellation Proprietary. Use of Operating Experience for License Renewal Implementation / Aging Management Revision 6 AR 01554173 Thermography Identified Hot Lead in MCC 36-1 Cubicle A5 09/13/2013 AR 04501726 Thermography Anomaly in Unit 3 MPT 05/31/2022 AR 04256329 Thermography Identified Hot Cables in Breaker 2/3-7856-1C2 06/13/2019 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
The staff also audited the description of the SLRA Electrical Cable Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements provided in the UFSAR supplement.
The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.3.1.1, Fatigue Monitoring Summary of Information in the Application. The SLRA states that AMP B.3.1.1, Fatigue Monitoring, is an existing preventive program with enhancements that is consistent with the program elements in GALL-SLR AMP X.M1, Fatigue Monitoring. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the program elements described in the applicants basis document.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
60 Relevant Documents Reviewed During the audit, the staff audited the applicants claim that the scope of program, preventive actions, detection of aging effects, monitoring and trending, acceptance criteria and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP, or will be consistent after implementation of the identified enhancements.
The staff found that, for the parameter monitored or inspected program element, sufficient information was not available to verify whether it was consistent with the corresponding program element of the GALL-SLR Report AMP. The staff will consider issuing RAIs in order to obtain the information necessary to verify whether this program element is consistent with the corresponding program element of the GALL-SLR Report AMP.
During the audit, the staff made the following observations. The applicants OE evaluation regarding the Fatigue Monitoring AMP indicates that, in place of the currently used FatiguePro, Version 3.0 (fatigue monitoring software) that utilizes the single stress term methodology for Document Title Revision / Date DR-PBD-AMP-X.M1 Program Basis Document Fatigue Monitoring Revision 1 6/19/2024 AR 04514409-75 Aging Management Program (AMP) Effectiveness Review Dresden Fatigue Monitoring AMP X.M1 12/7/2023 AR 01475576 DTP 07: U2/U3 HPCI Operational Cycles 2/14/2013 AR 00958725 LR B.1.34 AMP - FatiguePro Software Issues 8/28/2009 AR 04519687 Semi-Annual Fatigue and Transient Monitoring Program Results 8/30/2022 N/A Dresden Nuclear Power Station Subsequent License Renewal Operating Experience (OE) Review Process Review 9/17/2024 N/A DNPS Operating Experience Review Summary 9/17/2024 LR-AA-1709 Constellation Proprietary. Aging Management Reviews (AMR)
Revision 0 LR-AA-1702 Constellation Proprietary. Preparation of Basis Documents Revision 0 LR-AA-1701 Constellation Proprietary. License Renewal Process &
Definitions Revision 0 ER-AA-470 Constellation Proprietary. Fatigue and Transient Monitoring Program Revision 11 Structural Integrity Associates (SIA) 0901269.303 Dresden 2 Feedwater Nozzle Confirmatory Analysis Revision 0 12/16/2009
61 stress based fatigue monitoring, FatiguePro Version 4.0, which considers the six stress components, will be used for SLR. However, the staff noted that the use of the FatiguePro Version 4.0 is not identified as an enhancement to the Fatigue Monitoring AMP.
The staff also audited the description of the SLRA Fatigue Monitoring AMP provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.3.1.2, Neutron Fluence Monitoring Summary of Information in the Application. The SLRA states that AMP B.3.1.2, Neutron Fluence Monitoring, is an existing program that is consistent with the program elements in GALL-SLR Report AMP X.M2, Neutron Fluence Monitoring.
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date GE Hitachi Nuclear Energy, 008N0679 GEH Proprietary. Dresden Nuclear Power Station Unit 3 Subsequent License Report Pressure and Temperature Limits Report (PTLR)
Revision A GE Hitachi Nuclear Energy, 008N1119 GEH Proprietary. Dresden Nuclear Power Station Unit 2 Subsequent License Report Pressure and Temperature Limits Report (PTLR)
Revision A BWRVIP-321 BWR Vessel and Internals Project: Plan for Extension of the BWR Integrated Surveillance Program (ISP) Through the Second License Renewal (SLR)
Revision 1-A DR-PBD-AMP-X.M2 Neutron Fluence Monitoring Program Basis Document Revision 1 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP are consistent with the corresponding elements of the GALL-SLR Report AMP.
The staff also audited the description of the SLRA AMP Neutron Fluence Monitoring provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA AMP B.3.1.3, Environmental Qualification of Electric Equipment Summary of Information in the Application. The SLRA states that AMP B.3.1.3, Environmental Qualification of Electric Equipment, is an existing program with an enhancement that will be consistent with the program elements in GALL-SLR Report AMP X.E1, Environmental Qualification of Electric Equipment. At the time of the audit, the applicant had not yet fully developed the documents necessary to implement this enhanced program, and the staffs audit addressed only the program elements described in the applicants basis document, available procedures, and referenced documents.
Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
62 The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-PBD-AMP-X.E1 Program Basis Document - Environmental Qualification of Electric Equipment Revision1 DR-TLAABD (Part 2)
Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation - Dresden LR Section 4.4, Environmental Qualification of Electric Equipment Revision 0 EQ-40D Environmental Qualification of Automatic Valve Company (AVCo)
MSIV Solenoid Valves Assembly AC Solenoid, P/N 6910-010 and DC Solenoid, P/N 6910-020 Revision 11 EQ-80D Environmental Qualification of Barksdale Pressures Switch Series B2T-M12SS Revision 4 AR 04080012-27 Dresden Station B1.35 Environmental Qualification of Electric Components 7/26/2018 AR 02592021 NRC IN 2015-12, Unaccounted for Error Terms Associated with the Irradiation Testing and Environmental Qualification of Important-to-Safety Components 5/4/2016 AR 02614751 OE: NRC IN 2015-12 On Steris Unaccounted Dose Error Terms 06/08/2017 AR 00954985 Environmental Qualification (EQ) FASA-PM Frequency Deficiency 11/10/2009 AR 04845475 NRC ID: EPRI NP-1558 Activation Energy References (EQ) 03/14/2025 CC-AA-203 Constellation Proprietary. Environmental Qualification Program Revision 18 ER-AA-300-150 Constellation Proprietary. Cable Conditioning Monitoring Program Revision 8 MA-AA-723-500 Constellation Proprietary. Inspection of NON EQ Cables and Connections for Managing Adverse localized Environments Revision 13 NES-EIC-30.00 Constellation Proprietary. Environmental Qualification Engineering Revision 2 TID-EQ-01 Environmental Qualification Installation, Surveillance, Maintenance, Replacement of EQ Equipment Revision 0 TID-EQ-02 Environmental Qualification: Qualified Life Assessment Revision 0 TID-EQ-03 Environmental Qualification: Similarity Analysis of EQ Equipment Revision 0 TID-EQ-04 Environmental Qualification: Evaluation of the Design Basis Event (DBE) Simulation Revision 0 TID-EQ-05 Environmental Qualification Functional Performance Evaluation Revision 0 During the audit, the staff verified the applicants claim that the scope of program, preventive actions, parameters monitored or inspected, detection of aging effects, monitoring and trending, acceptance criteria, and corrective actions program elements of the SLRA AMP
63 will be consistent with the corresponding elements of the GALL-SLR Report AMP after implementation of the identified enhancement.
During the audit, the staff made the following observations:
The staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. The applicant explained how the data for environmental parameters were monitored and how ALEs were identified. The applicant also provided environmental qualification binders that have been revised to extend the qualified life of electrical components for the subsequent period of extended operation. For these environmental qualification binders, the staff observed that the applicant utilized analytical techniques to extend the qualification of the electrical components.
The staff requested the applicant explain how it has addressed concerns with lack of technical references for activation energies for certain materials that were initially provided in Electric Power Research Institute (EPRI) Report NP-1558, A review of Equipment Aging Theory and Technology, Revision 0. NP-1558, Revision 1, resulted in the removal of about 30% of the referenced activation energies due to lack of supporting documentation. The applicant mentioned that they were aware of the issues related to the removal of activation energies in this revision and has created a corrective action report (AR 04845475) to ensure the use of any activation energy values obtained from EPRI NP-1558, Revision 0, remain valid.
The staff also audited the description of the SLRA Environmental Qualification of Electric Equipment provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the GALL-SLR Report.
SLRA TLAA Section 4.1, Identification of Time-Limited Aging Analyses (TLAAs)
Summary of Information in the Application. SLRA Section 4.1, Identification of Time-Limited Aging Analyses (TLAAs), discusses the methodology for identifying TLAAs in the SLRA. The staff performed an audit to verify the implementation of the applicants methodology to identify TLAAs in accordance with 10 CFR Part 54. Issues identified but not resolved in this report will be addressed in the SE.
Audit Activities. During the audit, the staff reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. The table below lists documents that were reviewed by the staff and were found to be relevant to its review for TLAA identification. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 1 -
TLAA Identification - Dresden SLR Includes Attachments 1 through 14 Revision 0 Updated Final Safety Analysis Report Revision 13 ADAMS Accession No. ML21041A445 Submittal of Analytical Evaluation of Isolation Condenser Nozzle to Shell Weld Flaw Indications (ISI Weld 3/2/1302A-12/12-8)
64 Document Title Revision / Date GE-NE B13-02106-05 Technical Safety Evaluation Report - Jet pump sensing line -
Dresden Unit 2&3 - Quad Cities Unit 1&2 Revision 1 PMID 11970 WO 05095361 PMID 11967 WO 04712204 PMID 12416 WO 05364471 PMID 12147 WO 05257605 During the audit, the staff verified that the applicant has provided its basis and methodology for identifying TLAAs, as defined in 10 CFR 54.3(a), in accordance with 10 CFR 54.21(c)(1).
During the audit, the staff made the following observations:
The staff reviewed the DR-TLAABD, Part 1, and confirmed that current licensing basis and design basis documentation were searched to identify potential TLAAs.
o The staff noted that specific key words were used during the applicants search that would identify potential TLAAs. The staff noted that a comprehensive list of key words was used for the applicants search.
o The staff noted that keywords used were reasonable for identifying analyses associated with time-dependency and aging-related degradation.
Keywords included, but not limited to the following: fluence, life, cyclic, 40-year, exemption, corrosion of DR-TLAABD, Part 1, contains the applicants complete list of keywords The staff reviewed the DR-TLAABD, Part 1, and confirmed that each potential TLAA was reviewed against the TLAA criteria of 10 CFR 54.3(a) and those that met all six criteria were identified as TLAAs.
o of DR-TLAABD, Part 1 - contains the applicants complete documentation of its dispositioning of any potential analyses against the criteria of a TLAA in 10 CFR 54.3.
o 4 of DR-TLAABD, Part 1 - contains additional discussion on more complicated potential TLAAs and the basis for whether the analysis was or was not identified as a TLAA in the SLRA.
The staff reviewed the DR-TLAABD, Part 1 (including attachments) and confirmed that a search of docketed licensing correspondence, the operating license, and the UFSAR identified whether there were any active exemptions currently in effect pursuant to 10 CFR 50.12.
65 The staff reviewed the DR-TLAABD, Part 1 (including attachments) and confirmed that these exemptions were reviewed to determine whether the exemption was based on a TLAA.
o The staff confirmed that there is no identified 10 CFR 50.12 exemption that is currently in effect that is based upon a TLAA.
SLRA TLAA Section 4.2.1, Reactor Pressure Vessel and Internals Neutron Fluence Analyses Summary of Information in the Application. SLRA Section 4.2.1, Reactor Pressure Vessel and Internals Neutron Fluence Analyses, discusses the analyses for the reactor pressure vessel and reactor pressure vessel internals. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(ii).
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date GE Hitachi Nuclear Energy, 008N0679 Dresden Nuclear Power Station Unit 2 Subsequent License Report Pressure and Temperature Limits Report (PTLR)
Revision A GE Hitachi Nuclear Energy, 008N1109 Dresden Nuclear Power Station Unit 3 Subsequent License Report Pressure and Temperature Limits Report (PTLR)
Revision A BWRVIP-321 BWR Vessel and Internals Project: Plan for Extension of the BWR Integrated Surveillance Program (ISP) Through the Second License Renewal (SLR)
Revision 1-A DR-PBD-AMP-X.M2 Neutron Fluence Monitoring Program Basis Document Revision 1 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(ii).
The staff also audited the description of the SLRA TLAA Reactor Pressure Vessel and Internals Neutron Fluence Analyses provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the SRP-SLR.
SLRA TLAA Section 4.2.2, Reactor Pressure Vessel Upper-Shelf Energy (USE) Analyses Summary of Information in the Application. SLRA Section 4.2.2, Reactor Pressure Vessel Upper-Shelf Energy (USE) Analyses, discusses the analyses for material embrittlement due to neutron fluence and its effect on fracture toughness. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(ii).
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
66 Relevant Documents Reviewed Document Title Revision / Date N/A Dresden Nuclear Power Station, Units 2 and 3 Subsequent License Renewal Application April 2024 BWRVIP-74-A BWRVIP-74-A: BWR Vessel & Internals Project; BWR Reactor Pressure Vessel Inspection and Flaw Evaluation Guidelines for License Renewal June 2003 BWRVIP-135 BWR Vessel Internals Project Integrated Surveillance Program (ISP) Data Source Book and Plant Evaluations Rev 4 RG 1.99 Radiation Embrittlement of Reactor Vessel Materials Rev 2 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(ii).
During the audit, the staff made the following observations:
The staff verified that the material information (e.g., %Cu, %Ni, initial USE, margin values) for the RPV materials contained in LRA Tables 4.2.2-3, 4.2.2-4, 4.2.-5, 4.2.2-6 and 4.2.3-7 are:
o Consistent with the applicants current licensing basis (e.g. FSAR, license amendments associated with power uprates or pressure-temperature limits) or NRC approved topical reports (i.e., BWRVIP-86, Rev 1-A) o Or based on information from certified material test reports (CMTRs) or fabrication records for the specific material or weld type.
The staff noted that the licensee used equivalent margin analysis (EMA) to demonstrate that the USEs of controlling beltline materials are within acceptable range per BWRVIP-74-A because there is insufficient data available to establish unirradiated USE for Dresden Units 2 and 3 shells and welds.
o The surveillance plate and weld used to determine EMA are all of different %Cu values from those found in the vessels at Dresden. The licensee used RG 1.99, Rev. 2, Position 2.2 to determine the % decrease in USE based on neutron fluence and %Cu of the limiting material, representative of Dresden, Units 2 and 3.
The licensee is managing changes in USE through surveillance of capsule data outlined in BWRVIP-135, which assesses the surveillance data for the domestic BWR fleet obtained from the BWRVIP Integrated Surveillance Program.
All controlling components have toughness above the toughness of 59 ft-lb required by BWRVIP-74-A.
The staff also audited the description of the SLRA Reactor Pressure Vessel Upper-Shelf Energy (USE) Analyses provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in SRP-SLR.
67 SLRA TLAA Section 4.2.3, Reactor Pressure Vessel Adjusted Reference Temperatures (ART) Analyses Summary of Information in the Application. SLRA Section 4.2.3, Reactor Pressure Vessel Adjusted Reference Temperature (ART) Analyses, discusses the analyses for the material chemistry and fluence of the reactor vessel shell and welds and how the fracture toughness of these materials have changed, represented by the adjusted reference ductile to brittle transition temperature. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(ii).
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date N/A Dresden Nuclear Power Station, Units 2 and 3 Subsequent License Renewal Application April 2024 BWRVIP-74-A BWRVIP-74-A: BWR Vessel & Internals Project; BWR Reactor Pressure Vessel Inspection and Flaw Evaluation Guidelines for License Renewal June 2003 No. 77-2258-00 BAW-2258 January 1996 BWRVIP-135 BWR Vessel Internals Project Integrated Surveillance Program (ISP) Data Source Book and Plant Evaluations Rev 4 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(ii).
During the audit, the staff made the following observations:
The staff verified that the material information (e.g., initial RTNDT, %Cu, and %Ni) for the RPV materials contained in SLRA Tables 4.2.3-1, 4.2.3-2, 4.2.3-3, and 4.2.3-4 are:
o Consistent with the applicants current licensing basis (e.g. FSAR, license amendments associated with power uprates or pressure-temperature limits) or NRC approved topical reports (i.e., BWRVIP-86, Rev 1-A) o Or based on information from certified material test reports (CMTRs) or fabrication records for the specific material or weld type.
The licensee noted that the controlling weld in Unit 2 is the electroslag axial weld at azimuthal angle 317° (Heat No. W8349) on Shell Ring 2. The controlling weld in Unit 3 is the electroslag axial weld at azimuthal angle 317° (Unidentified heat no.) on Shell Ring 1 and 142° (Heat No. 37A334) on Shell Ring 2.
The licensee needed to correct references to Unit 1 in SLRA Table 4.2.3-1 of the application, changing this to Unit 2, as well as correcting the Shell Rings referenced for Unit 2.
The staff noted that SLRA Table 4.2.3-4 discusses the applicants adjustment for ART when considering surveillance data. The staff verified that the applicants assessment of surveillance data contained in BWRVIP-135, Revision 4 was performed in accordance with RG 1.99, Revision 2, for the following reactor pressure vessel material:
68 o
Heat No. W8349 The staff also audited the description of the SLRA Reactor Pressure Vessel Adjusted Reference Temperature (ART) Analyses provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in SRP-SLR.
SLRA TLAA Section 4.2.4, Reactor Pressure Vessel Pressure-Temperature (p-T) Limits Summary of Information in the Application. SLRA Section 4.2.4, Reactor Pressure Vessel Pressure-Temperature (P-T) Limits, discusses the analysis for the fracture toughness that sets pressure and temperature limits for the reactor pressure vessel to maintain adequate safety margin during operation. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(iii).
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date N/A Dresden Nuclear Power Station, Units 2 and 3 Subsequent License Renewal Application April 2024 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(iii).
During the audit, the staff made the following observations:
The licensee states they will manage the P-T Limits located in the Technical Specifications through periodic LARs via 10 CFR 50.90 to amend the P-T Limits as necessary.
The staff also audited the description of the SLRA Reactor Pressure Vessel Pressure-Temperature (P-T) Limits provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in SRP-SLR.
SLRA TLAA Section 4.2.5, Reactor Pressure Vessel Circumferential Weld Failure Probability Analyses, and SLRA Section 4.2.6, Reactor Pressure Vessel Axial Weld Failure Probability Analyses Summary of Information in the Application. SLRA Section 4.2.5, Reactor Pressure Vessel Circumferential Weld Failure Probability Analyses, and SLRA Section 4.2.6, Reactor Pressure Vessel Axial Weld Failure Probability Analyses, discusses the failure probability analyses associated with neutron embrittlement of the RPV circumferential and axial welds, respectively.
The applicant dispositioned the TLAAs in accordance with 10 CFR54.21(c)(1)(iii) and 10 CFR54.21(c)(1)(ii), respectively.
Audit Activities. The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAAs. The staff will document its review of this information in the SE.
69 Relevant Documents Reviewed Document Title Revision / Date BWRVIP-329-A BWR Vessels and Internals Program: Updated Probabilistic Fracture Mechanics Analyses for BWR RPV Welds to Address Extended Operations December 2021 BWRVIP-05 BWR Vessels and Internals Project: BWR Reactor Pressure Vessel Shell Weld Inspection Recommendations September 1995 DR-TLAABD Dresden Power Station License Renewal Project - TLAA Basis Document - Part 2 - TLAA Evaluation Revision 0 During the audit of the TLAAs, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(iii) and 10 CFR 54.21(c)(1)(ii) for the failure probability analyses associated with the RPV circumferential and axial welds, respectively.
During the audit, the staff made the following confirmations and observations:
The plant-specific reactor pressure vessel dimensions for Units 2, and 3, used in the applicants assessment of these TLAAs (DR-TLAABD), are within the limits of applicability established in Table 5-1 of BWRVIP-329-A.
The staff confirmed, based on information in applicants assessment of these TLAAs (DR-TLAABD) and SLRA Tables 4.2.3-1 through Table 4.2.3-4, that the limiting plate, circumferential weld, and axial weld were addressed.
o Based on information in SLRA Tables 4.2.3-1 through Table 4.2.3-4, the staff confirmed the following regarding the limiting RPV materials at Unit 2:
limiting plate - Heat B4065-1
circumferential weld - Heat 71249/8504
axial weld - Heat 34A167/3496 o
Based on information in SLRA Tables 4.2.3-1 through Table 4.2.3-4, the staff confirmed the following regarding the limiting RPV materials at Unit 3:
limiting plate - Heat A0237-1
circumferential weld - Heat 299L44/8650
axial weld - Heat 34A167/3496 The plant-specific end-of-interval RTmax values for the limiting plate, circumferential weld, and axial weld for Units 2, and 3, were calculated based on material properties of the reactor pressure vessel based on 67 EFPY.
The plant-specific end-of-interval RTmax values for the limiting plate, circumferential weld, and axial weld for Units 2, and 3, were calculated consistent with the methods in BWRVIP-329-A.
The plant-specific end-of-interval RTmax values for the limiting plate, circumferential weld, and axial weld, for Units 2 and 3, were less than the corresponding limiting RTmax value for plate materials, circumferential welds, and axial welds in BWRVIP-329-A.
70 The staff also audited the description of the TLAA for the Reactor Pressure Vessel Circumferential Weld Failure Probability Analyses, and the Reactor Pressure Vessel Axial Weld Failure Probability Analyses provided in the UFSAR supplement. The staff verified that these descriptions are consistent with the description provided in SRP-SLR.
SLRA TLAA Section 4.2.7, Reactor Pressure Vessel Reflood Thermal Shock Analysis Summary of Information in the Application. SLRA Section 4.2.7, Reactor Pressure Vessel Reflood Thermal Shock Analysis, discusses the analysis for a postulated post-LOCA core reflood thermal shock to the reactor pressure vessel. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(ii).
Audit Activities. The staff reviewed OE documentation contained in the SLRA and ePortal, including descriptions of disposition of indications found in core shroud welds.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD TLAA Basis Document - Part 2 - TLAA Evaluation Revision 0 007N2347 Task T0303 - RPV Fracture Toughness Evaluation Revision 0 June 2023 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(ii).
The staff also audited the description of the SLRA A.4.2.10, Core Shroud Reflood Thermal Shock Analysis, provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the SRP-SLR for plant-specific TLAAs.
SLRA TLAA Section 4.2.8, Core Shroud Reflood Thermal Shock Analysis Summary of Information in the Application. SLRA Section 4.2.8, Core Shroud Reflood Thermal Shock Analysis, discusses the analysis for a postulated LPCI transient on the core shroud. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(i).
Audit Activities. The staff reviewed OE documentation contained in the SLRA and ePortal, including descriptions of the disposition of indications found in core shroud welds.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD TLAA Basis Document - Part 2 - TLAA Evaluation Revision 0
71 007N2163 Task T0313 - RPV Flux Evaluation - Final Task Report Revision 0 December 2022 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i).
The staff also audited the description of the SLRA A.4.2.10, Core Shroud Reflood Thermal Shock Analysis, provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the SRP-SLR for plant-specific TLAAs.
SLRA TLAA Section 4.2.9, Jet Pump Beam Bolt and Access Hole Cover Bolt Preload Relaxation Analyses Summary of Information in the Application. SLRA Section 4.2.9, Jet Pump Beam Bolt and Access Hole Cover Bolt Preload Relaxation Analyses, discusses the analyses for the RPV jet pump beam bolts and the Unit 2 access hole cover bolts subject to loss of preload due to irradiation. The applicant dispositioned the TLAA in accordance with 10 CFR 54.21(c)(1)(i).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. The staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD TLAA Basis Document - Part 2 - TLAA Evaluation Revision 0 GE 007N5479 Dresden 2 & 3 Power Station Licensing Renewal RPV Internal Analysis of Preloaded Joints Revision 1 GE 0000-0135-4594 Dresden 2 & 3 and Quad Cities 1 & 2 Jet Pump Beam Bolt Fluence Evaluation Revision 0 GE B11-00546-00 Quad Cities 1 and 2 and Dresden 2 and 3 Replacement Access Hole Cover Stress Analysis N/A GE 25A5191 Access Hole Cover Design Specification Revision 2 GE Y1002A651 NI-CR-FE Alloy X-750, Irradiated Revision 1 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i) for SLRA Section 4.2.9.
During the audit, the staff made the following observations:
The staff verified that the maximum projected 80-year fluence values located at the jet pump beam bolts were determined to be 1.18E19 n/cm² and 1.17E19 n/cm2 for Units 2 and 3, respectively (i.e., GE 007N5479), consistent with the information provided in SLRA Section 4.2.9. The staff confirmed that these fluence values for Units 2 and 3 are
72 less than the original design analysis (i.e., GE 0000-0135-4594) of the jet pump beam bolts (i.e., 1.27E19 n/cm2).
The staff noted that the Unit 2 access holes have been modified to a bolted design versus the original welded configuration, whereas no modification was made on Unit 3; therefore, the potential of loss of preload due to the effects of fluence is applicable to Unit 2, only.
The staff verified that the maximum projected 80-year fluence values located at the Unit 2 access hole cover bolts was determined to be 1.37E19 n/cm2 (i.e., GE 007N5479),
consistent with the information provided in SLRA Section 4.2.9. The staff confirmed that this fluence value is less than the original design analysis (i.e., GE B11-00546-00, GE 25A5191, and GE Y1002A651) of the Unit 2 access hole cover bolts (i.e., 9.00E19 n/cm2).
The staff also audited the description of the Jet Pump Beam Bolt and Access Hole Cover Bolt Preload Relaxation Analyses TLAA in SLRA Section A.4.2.11 provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the SRP-SLR.
SLRA TLAA Section 4.2.10, Jet Pump Auxiliary Wedge Assembly Loss of Preload Analysis Summary of Information in the Application. SLRA Section 4.2.10, Jet Pump Auxiliary Wedge Assembly Loss of Preload Analysis, discusses the analyses for the DNPS jet pump auxiliary wedge assemblies subject to loss of preload due to irradiation. The applicant dispositioned the TLAA in accordance with 10 CFR 54.21(c)(1)(i).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. The staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD TLAA Basis Document - Part 2 - TLAA Evaluation Revision 0 GE 007N5479 Dresden 2 & 3 Power Station Licensing Renewal RPV Internal Analysis of Preloaded Joints Revision 1 GE 26A6769 Aux Wedge Design Specification Revision 0 ER-DR-331-1001 Constellation Proprietary. Dresden Reactor Pressure Vessel and Internals Program Bases Document Revision 10 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i) for SLRA Section 4.2.10.
During the audit, the staff made the following observations:
73 The staff noted that five total jet pump assemblies have had auxiliary wedge assemblies installed at DNPS Units 2 and 3.
The staff verified that the maximum projected 80-year fluence value at the limiting auxiliary wedge assembly for Unit 2 was determined to be 2.80E18 n/cm2 at the end of the SPEO (GE 007N5479), consistent with the information provided in SLRA Section 4.2.10.
The staff also verified that the maximum projected 80-year fluence value at the limiting auxiliary wedge assembly for Unit 3 was determined to be 2.78E18 n/cm2 at the end of the SPEO (GE 007N5479), consistent with the information provided in SLRA Section 4.2.10.
The staff confirmed that the maximum projected fluence values for Unit 2 and Unit 3 are less than the original design analysis (i.e., GE 26A6769) of the auxiliary wedges (i.e.,
1.40E20 n/cm2).
The staff also audited the description of the Jet Pump Auxiliary Wedge Assembly Loss of Preload Analysis TLAA in SLRA Section A.4.2.12, provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the SRP-SLR.
SLRA TLAA Section 4.2.11, Unit 2 Jet Pump Riser Repair/Mitigation Clamps Loss of Preload Analysis Summary of Information in the Application. SLRA Section 4.2.11, Unit 2 Jet Pump Riser Repair/Mitigation Clamps Loss of Preload Analysis, discusses the analyses for the DNPS Unit 2 jet pump riser brace clamps subject to loss of preload due to irradiation. The applicant dispositioned the TLAA in accordance with 10 CFR 54.21(c)(1)(i).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. The staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD TLAA Basis Document - Part 2 - TLAA Evaluation Revision 0 GE 26A5919 Jet Pump Riser Brace Repair and Frequency Mitigation Revision 0 EC 340795 WO 00499890 Dresden Unit 2 Jet Pump Riser Brace Repair and Vibration Mitigation Clamp Installation 10/30/2003 GE 007N5479 Dresden 2 & 3 Power Station Licensing Renewal RPV Internal Analysis of Preloaded Joints Revision 1
74 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i) for SLRA Section 4.2.11.
During the audit, the staff made the following observations:
The staff noted that in 2003, clamps were installed on all DNPS Unit 2 jet pump riser braces and that these clamps use bolts to maintain proper clamping force; and therefore, are subject to loss of preload due to irradiation.
The staff verified that the maximum projected 80-year fluence value at the limiting Unit 2 jet pump riser brace location was determined to be 2.43E17 n/cm2 (GE 007N5479),
consistent with the information provided in SLRA Section 4.2.11.
The staff confirmed that this fluence value is less than the original design analysis (i.e.,
GE 26A5919) of the Unit 2 jet pump riser braces (i.e., 5E20 n/cm2).
The staff also audited the description of the Unit 2 Jet Pump Riser Repair/Mitigation Clamps Loss of Preload Analysis TLAA in SLRA Section A.4.2.13, provided in the UFSAR supplement.
The staff verified that this description is consistent with the description provided in the SRP-SLR.
SLRA TLAA Section 4.2.12, Unit 2 and 3 Core Spray Replacement Piping Bolting Loss of Preload Evaluation Summary of Information in the Application. SLRA Section 4.2.12, Unit 2 and 3 Core Spray Replacement Piping Bolting Loss of Preload Evaluation, discusses the analysis for the Core Spray Replacement Piping Bolting. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(i). To verify that the applicant provided a basis to support its disposition of the TLAA, the staff audited the TLAA.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD, Part 1 Time-Limited Aging Analysis (TLAA) Basis Document - Part 1 - TLAA Identification - Dresden LR Revision 0 April 2024 DR-TLAABD, Part 2 TLAA Basis Document - Part 2 - TLAA Evaluation Revision 0 April 2024 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i). If further information is needed to complete the staffs SE input, the staff will consider issuing RAIs.
The staff also audited the description of the SLRA Unit 2, and 3 Core Spray Replacement Piping Bolting Loss of Preload Evaluation provided in the UFSAR supplement. The staff verified that
75 this description is consistent with the description provided in the SRP-SLR. If further information is needed to complete the staffs SE input, the staff will consider issuing RAIs.
SLRA TLAA Section 4.2.13, Core Shroud Repair Stabilizer Assembly Bracket Preload Relaxation Analysis Summary of Information in the Application. SLRA Section 4.2.13, Core Shroud Repair Stabilizer Assembly Bracket Preload Relaxation Analysis, discusses the analyses for the DNPS core shroud tie rod stabilizer assemblies subject to loss of preload due to irradiation. The applicant dispositioned the TLAA in accordance with 10 CFR 54.21(c)(1)(i).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. The staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD TLAA Basis Document - Part 2 - TLAA Evaluation Revision 0 GE 007N5479 Dresden 2 & 3 Power Station Licensing Renewal RPV Internal Analysis of Preloaded Joints Revision 1 GE 25A5688 Shroud Stabilizer Hardware Design Specification Revision 2 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i) for SLRA Section 4.2.13.
During the audit, the staff made the following observations:
The staff noted that a core shroud repair was installed on Unit 2 in 1995 and on Unit 3 in 1997 and that the design accounted for preload relaxation of the core shroud tie rod stabilizer assemblies due to irradiation of 3.12E20 n/cm2 (i.e., GE 25A5688), consistent with the information provided in SLRA Section 4.2.13.
The staff verified that the peak projected 80-year fluence values for the shroud stabilizer tie rod and spring fluence values were less than the original design analysis referenced above.
The staff also audited the description of the Core Shroud Repair Stabilizer Assembly Bracket Preload Relaxation Analysis TLAA in SLRA Section A.4.2.15, provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the SRP-SLR.
SLRA TLAA Section 4.3.1, Transient and Cumulative Usage Projections for 80 Years Summary of Information in the Application. SLRA Section 4.3.1, Transient Cycle and Cumulative Usage Projections for 80 Years, discusses the 80-year transient cycle and
76 cumulative usage projections for fatigue analyses. The cumulative usage projections include the 80-year projections for cumulative usage factor (CUF) and environmentally adjusted CUF (CUFen) for the reactor coolant pressure boundary components.
The applicant did not identify the transient cycle and cumulative usage projections as a TLAA because (1) the transient cycle projections are used only as input to fatigue TLAAs and (2) the specific dispositions of fatigue TLAAs, which involve transient cycles, CUF or CUFen, are separately described in SLRA Sections 4.3.2 through 4.3.7. To verify the adequacy of the projections of transient cycles, CUF and CUFen, the staff audited the 80-year cycle and cumulative usage projections. The staff will address issues identified but not resolved in this audit report in the SE.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the 80-year cycle and cumulative usage projections for fatigue analyses. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation Dresden LR Revision 0 4/2/2024 Structural Integrity Associates (SIA) FP-DRES-413P Cycle Based Fatigue Report for the Transient and Fatigue Monitoring System at Dresden Generating Station Revision 1 8/14/2023 SIA 2200483.308 SI:FatiguePro4 Baseline, Cycle, Fatigue and EAF Projections as of 12/31/2022 for Dresden Unit 2 Revision 2 1/31/2024 SIA 2200483.309 SI:FatiguePro4 Baseline, Cycle, Fatigue and EAF Projections as of 6/30/2022 for Dresden Unit 3 Revision 1 1/30/2024 SIA 2200483.301 Dresden Cycle and Fatigue 80-Year Projections Revision 1 5/15/2023 N/A Dresden Nuclear Power Station Subsequent License Renewal Operating Experience (OE) Review Process Review 9/17/2024 N/A DNPS Operating Experience Review Summary 9/17/2024 During the audit of the 80-year cycle and cumulative usage projections, the staff verified that the applicant has provided its basis that supports the adequacy of cycle and cumulative usage projections. However, the staff found that sufficient information was not available to complete its
77 review of the projections. In order to obtain the necessary information, the staff will consider issuing RAIs.
During the audit, the staff made the following observations. SLRA Tables 4.3.1-1 and 4.3.1-2 indicate the Unit 2 turbine roll and increase to rated power and the Units 2 and 3 main steam fill during flood-up transients are projected to exceed the design transient cycles (occurrences) before 80 years. In comparison, the applicant dispositioned the fatigue TLAAs for the isolation condensers and the Unit 2 replacement core spray piping in accordance with 10 CFR54.21(c)(1)(i), as discussed in SLRA Sections 4.3.7 and 4.7.5, respectively. Given the TLAA dispositions for the components in accordance with 10 CFR54.21(c)(1)(i) (i.e., not using cycle projections or Fatigue Monitoring AMP), the staff needs clarification on whether the 80-year projected cycles of the Unit 2 turbine roll and increase to rated power transient and the Units 2 and 3 main steam fill during flood-up transient, which exceed the design cycles, may affect the validity of these TLAA dispositions (e.g., resulting in the 80-year CUF values greater than 1.0).
The staff also audited the description of the 80-year cycle and cumulative usage projections provided in the UFSAR supplement. The staff verified that this description is consistent with the guidance in SRP-SLR Section 4.3.2.2.
SLRA TLAA Section 4.3.2, ASME Section III, Class 1 Fatigue Analyses Summary of Information in the Application. SLRA Section 4.3.2, ASME Section III, Class 1 Fatigue Analyses discusses the fatigue analyses for ASME Code Section III Class 1 components for 80 years of operation. This section mainly addresses the CUF analyses and the environmental fatigue analyses (also called environmentally assisted fatigue (EAF) analyses) for the Class 1 components are separately discussed in SLRA Section 4.3.3. The applicant dispositioned the TLAAs for the Class 1 components in accordance with 10 CFR54.21(c)(1)(iii).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the Class 1 fatigue analyses. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation Dresden LR Revision 0 4/2/2024 SIA 2200483.308 SI:FatiguePro4 Baseline, Cycle, Fatigue and EAF Projections as of 12/31/2022 for Dresden Unit 2 Revision 2 1/31/2024
78 During the audit of the TLAAs, the staff verified that the applicant has provided its basis that supports its disposition of 10 CFR 54.21(c)(1)(iii).
The staff also audited the description of the Class 1 fatigue TLAAs provided in the UFSAR supplement. The staff verified that this description is consistent with the guidance in SRP-SLR Section 4.3.2.2.
SLRA TLAA Section 4.3.3, Environmental Fatigue Analyses For RPV and Class 1 Piping Summary of Information in the Application. SLRA Section 4.3.3, Environmental Fatigue Analyses for RPV and Class 1 Piping, discusses the environmental fatigue TLAAs for the reactor pressure vessel and ASME Code Section III, Class 1 piping systems. Environmental fatigue is also called EAF. The applicant dispositioned the EAF TLAAs in accordance with 10 CFR54.21(c)(1)(iii).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the EAF TLAAs for the reactor pressure vessel and Class 1 piping systems. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation Dresden LR Revision 0 4/2/2024 Document Title Revision / Date SIA 2200483.309 SI:FatiguePro4 Baseline, Cycle, Fatigue and EAF Projections as of 6/30/2022 for Dresden Unit 3 Revision 1 1/30/2024 Dresden UFSAR Section 5.4.1.2.2 Reactor Recirculation Pumps, Valves, and Piping Revision 11 June 2015 N/A Dresden Nuclear Power Station Subsequent License Renewal Operating Experience (OE) Review Process Review 9/17/2024 N/A DNPS Operating Experience Review Summary 9/17/2024
79 Document Title Revision / Date SIA 2200483.308 SI:FatiguePro4 Baseline, Cycle, Fatigue and EAF Projections as of 12/31/2022 for Dresden Unit 2 Revision 2 1/31/2024 SIA 2200483.309 SI:FatiguePro4 Baseline, Cycle, Fatigue and EAF Projections as of 6/30/2022 for Dresden Unit 3 Revision 1 1/30/2024 SIA 2200483.303P Environmentally Assisted Fatigue Screening for Dresden Revision 2 8/11/2023 SIA 2200483.305P Environmentally Assisted Fatigue Calculations for Sentinel Locations at Dresden Revision 1 8/14/2023 SIA 0901269.303 Dresden 2 Feedwater Nozzle Confirmatory Analysis Revision 0 12/16/2009 During the audit of the TLAAs, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(iii). However, the staff found that sufficient information was not available to complete its review of the applicants basis for the TLAA disposition. In order to obtain the necessary information, the staff will consider issuing RAIs.
During the audit, the staff made the following observations.
SLRA Section 4.3.3 explains that the screening evaluation uses bounding environmental fatigue correction factor (Fen) and environmentally adjusted cumulative usage factor (CUFen) values. However, the SLRA does not clearly discuss how the bounding Fen and CUFen values are calculated (e.g., how the applicant determined the bounding sulfur content for steels, temperature and strain rate in the screening evaluation). SLRA Section 4.3.3 also indicates that a detailed EAF evaluation was performed to refine the CUFen values to reduce the excessive conservatism associated with the screening CUFen values. However, the SLRA does not clearly discuss how the applicant refined the CUFen values for the limiting locations.
The following SIA report indicates that in the detailed EAF analysis for the limiting locations, the Fen calculations use the average temperature approach considering the threshold temperature for each material type (
Reference:
SIA 2200483.305P, Environmentally Assisted Fatigue Calculations for Sentinel Locations at Dresden, Revision 1). However, the SLRA does not clearly discuss the following: (1) whether the average temperature approach is used only for simple, linear transients; and (2) if not, why the conservatism of the applicants approach is comparable to or greater than that of the modified rate approach described in NUREG/CR-6909, Rev. 1, Section 4.4 (e.g., plant-specific demonstration of the adequacy of the applicants approach).
SLRA Table 4.3.1-3 describes the limiting EAF locations and their 80-year projected CUFen values. However, SLRA Table 4.3.1-3 does not clearly describe the thermal zones
80 evaluated in the EAF analysis and specific materials of fabrication associated with the limiting EAF locations.
The staff also audited the description of the EAF TLAAs for the reactor pressure vessel and Class 1 piping systems provided in the UFSAR supplement. The staff verified that this description is consistent with the guidance in SRP-SLR Section 4.3.2.2.
SLRA TLAA Section 4.3.4, ASME Section III, Class 1 Fatigue Waivers Summary of Information in the Application. SLRA Section 4.3.4, ASME Section III, Class 1 Fatigue Waivers discusses the fatigue waiver TLAAs for ASME Code Section III Class 1 components. The applicant dispositioned the TLAAs in accordance with 10 CFR54.21(c)(1)(ii).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the fatigue waiver analyses for the Class 1 components. The staff will document its review of this information in the SE.
Relevant Documents Reviewed During the audit of the TLAAs, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(ii). However, the staff found that sufficient information was not available to complete its review of the applicants basis for the TLAA disposition. In order to obtain the necessary information, the staff will consider issuing RAIs.
During the audit, the staff made the following observations.
SLRA Table 4.3.4-2 describes the number of transient cycles assumed in the fatigue waiver reevaluation for 80 years of operation for the ASME Code Section III, N-415.1 criteria for fatigue waiver (i.e., N-415.1(a) through (e)). However, SLRA Table 4.3.4-2 does not clearly describe the 80-year projected cycles in comparison with the cycles assumed in the 80-year fatigue waiver reanalysis.
Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation Dresden LR Revision 0 4/2/2024 SIA 22000483.301 Dresden Cycle and Fatigue 80-Year Projections Revision 1 5/15/2023 SAI 2200483.302 Fatigue Exemptions (Waivers) for Dresden Class 1 Components Revision 2 8/11/2023
81 In addition, SLRA Table 4.3.4-2 does not describe the following information on the N-415.1(f) criterion regarding significant mechanical load fluctuations: (1) transients assumed in the fatigue waiver reanalysis, (2) transient cycles assumed in the existing waiver analysis, (3) transient cycles assumed in the fatigue waiver reanalysis, (4) 80-year projected cycles of the evaluated transients and (5) whether the fatigue waiver criterion is met in the fatigue waiver reanalysis.
The staff also audited the description of the fatigue waiver TLAAs for the ASME Code Section III Class 1 components provided in the UFSAR supplement. The staff verified that this description is consistent with the guidance in SRP-SLR Section 4.3.2.2.
SLRA TLAA Section 4.3.5, ASME Section III, Class 2 & 3, and ANSI B31.1 Allowable Stress Analyses and Associated HELB Analyses Summary of Information in the Application. SLRA Section 4.3.5, ASME Section III, Class 2 & 3, and ANSI B31.1 Allowable Stress Analyses and Associated HELB Analyses discusses the allowable stress and HELB TLAAs for non-Class 1 piping systems. The allowable stress TLAAs are implicit fatigue analyses, which do not involve an explicit analysis of cumulative fatigue usage, but rather cyclic loading is considered in a simplified manner in the design process by using a stress range reduction factor for the allowable expansion stress based on the transient cycles. The HELB TLAAs also use the cycle-dependent allowable stress as part of the criteria for HELB location postulation. The applicant dispositioned the TLAAs in accordance with 10 CFR54.21(c)(1)(i).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the allowable stress and HELB TLAAs for the non-Class 1 piping systems. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation Dresden LR Revision 0 4/2/2024 N/A Dresden SLR TLAABD Part 2, TLAA Pipe Segment Review 9/10/2024 SIA 22000483.301 Dresden Cycle and Fatigue 80-Year Projections Revision 1 5/15/2023
82 During the audit of the TLAAs, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i). However, the staff found that sufficient information was not available to complete its review of the TLAAs. In order to obtain the necessary information, the staff will consider issuing RAIs.
During the audit, the staff made the following observations. SLRA Table 4.3.5-2 describes the conservative 80-year projected cycles for the non-Class 1 piping systems that are affected by the transients other than the reactor coolant system transients listed in SLRA Tables 4.3.1-1 and 4.3.1-2. However, SLRA Section 4.3.5 does not clearly describe how the 80-year projected cycles were determined (e.g., based on piping system design information, plant operation procedures, test requirements, UFSAR information and specific system-level knowledge).
The staff also audited the description of the allowable stress and HELB TLAAs for the non-Class 1 piping systems provided in the UFSAR supplement. The staff verified that this description is consistent with the guidance in SRP-SLR Section 4.3.2.2.
SLRA TLAA Section 4.3.6, Reactor Pressure Vessel Internals Fatigue Analyses Summary of Information in the Application. SLRA Section 4.3.6, Reactor Pressure Vessel Internals Fatigue Analyses discusses the fatigue analysis for the reactor vessel internal (RVI) components. The applicant dispositioned the fatigue TLAA for the core shroud support in accordance with 10 CFR54.21(c)(1)(iii). In addition, the applicant dispositioned the fatigue TLAA for the Unit 2 jet pump riser brace (JPRB) clamps in accordance with 10 CFR54.21(c)(1)(ii).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the fatigue TLAAs for the RVI components. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation Dresden LR Revision 0 4/2/2024 SIA 2200483.308 SI:FatiguePro4 Baseline, Cycle, Fatigue and EAF Projections as of 12/31/2022 for Dresden Unit 2 Revision 2 1/31/2024 SIA 2200483.309 SI:FatiguePro4 Baseline, Cycle, Fatigue and EAF Projections as of 6/30/2022 for Dresden Unit 3 Revision 1 1/30/2024
83 Document Title Revision / Date GE 007N7207 Dresden Unit 2 Jet Pump Riser Brace Repair and Core Spray Line Lower Sectional Replacement Service Life Extension Evaluation Revision 0 June 2023 During the audit of the TLAAs, the staff verified that the applicant has provided its basis that supports its disposition of 10 CFR 54.21(c)(1)(iii) for the core shroud support and its disposition of 10 CFR 54.21(c)(1)(ii) for the Unit 2 JPRB clamps. However, the staff found that sufficient information was not available to complete its review of the applicants basis for its TLAA disposition. In order to obtain the necessary information, the staff will consider issuing RAIs.
During the audit, the staff made the following observations.
SLRA Section 4.3.6.2 provides the following explanation regarding the JPRB clamps. During the fall 2001 refueling outage for DNPS Unit 2, a crack was detected in the JPRB for jet pumps 9/10. The SLRA also explains that a mechanical clamping system designed to structurally replace these welds was installed on both jet pump risers in 2003. However, the SLRA does not clearly discuss which specific welds of the jet pump assembly are structurally replaced by the JPRB clamps.
In addition, the staff noted that typically two jet pumps share one riser pipe. However, the SLRA explains that the mechanical clamp system was installed on both jet pump risers of the jet pumps 9/10, indicating that the jet pumps 9/10 may have two riser pipes rather than one riser pipe. SLRA Section 4.3.6.2 further explains that the JPRB clamps were also installed on the other 19 JPRBs of Unit 2 to preclude high cycle fatigue cracking concerns. However, the SLRA section does not clearly discuss the following items related to the JPRB clamps; (1) how many jet pump riser pipes are installed inside the Unit 2 reactor pressure vessel; (2) how many JPRB clamps are subject to the fatigue TLAA; (3) frequency and method of the periodic inspections for the JPRB clamps; and (4) whether the results of these inspections confirm the absence of cracking in the clamps due to fatigue or other degradation mechanisms (e.g., SCC).
The staff also audited the description of the fatigue TLAAs for the RVI components provided in the UFSAR supplement. The staff found that sufficient information was not available to determine whether the description provided in the UFSAR supplement was an adequate description of the fatigue TLAA for the JPRB clamps. Specifically, the staff needs to clarify how many JPRB clamps are subject to the fatigue TLAA. The staff will consider issuing an RAI in order to obtain the information necessary to verify the sufficiency of the UFSAR supplement description in relation to the fatigue TLAA discussed above.
SLRA TLAA Section 4.3.7, Fatigue Analysis of the Isolation Condensers Summary of Information in the Application. SLRA Section 4.3.7, Fatigue Analysis of the Isolation Condensers discusses the fatigue analysis for the isolation condensers. The applicant dispositioned the fatigue TLAA for the isolation condensers in accordance with 10 CFR54.21(c)(1)(i).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
84 For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the fatigue TLAA for the isolation condensers. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation Dresden LR Revision 0 4/2/2024 KPA-SWC-67-131 Stress Report Dresden 2 and 3 Isolation Condenser Revision 0 September 1967 During the audit of the TLAAs, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(ii) for the isolation condensers.
However, the staff found that sufficient information was not available to complete its review of the applicants basis for its TLAA disposition. In order to obtain the necessary information, the staff will consider issuing RAIs.
During the audit, the staff made the following observations.
SLRA Section 4.3.7 explains the specification for the isolation condensers and the supporting system piping and components requires analysis for 250 shutdown depressurization occurrences (cycles) in the original design life of 40 years. In contrast, SLRA Tables 4.3.1-1 and 4.3.1-2, which address the design transients for Units 1 and 2 respectively, indicate that the number of design cycles for the operation of isolation condenser transient is 240 cycles. This number is slightly less than the 250 cycles of the shutdown depressurization transient discussed above. The staff needs to resolve this apparent inconsistency between the design cycles (i.e.,
240 cycles versus 250 cycles).
The staff also audited the description of the fatigue TLAA for the isolation condensers in the UFSAR supplement. The staff found that sufficient information was not available to determine whether the description provided in the UFSAR supplement was an adequate description of the fatigue TLAA for the isolation condensers. Specifically, the staff needs to clarify the number of the design cycles for the isolation condensers as discussed above. The staff will consider issuing an RAI in order to obtain the information necessary to verify the sufficiency of the UFSAR supplement description in relation to the fatigue TLAA for the isolation condensers.
SLRA TLAA Section 4.4, Environmental Qualification of Electric Equipment Summary of Information in the Application. SLRA Section 4.4, Environmental Qualification of Electric Equipment, discusses the thermal, radiation, and cyclical aging analyses of plant electrical and instrumentation and control (I&C) components. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(iii).
85 Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD (Part 2)
Time-Limited Aging Analysis (TLAA) Basis Document -
Part 2 - TLAA Evaluation - Dresden LR Section 4.4, Environmental Qualification of Electric Equipment Revision 0 DR-PBD-AMP-X.E1 Program Basis Document - Environmental Qualification of Electric Equipment.
Revision1 EQ-40D Environmental Qualification of Automatic Valve Company (AVCo) MSIV Solenoid Valves Assembly AC Solenoid, P/N 6910-010 and DC Solenoid, P/N 6910-020 Revision 11 EQ-80D Environmental Qualification of Barksdale Pressures Switch Series B2T-M12SS Revision 4 AR 04080012-27 Dresden Station B1.35 Environmental Qualification of Electric Components 7/26/2018 AR 02592021 NRC IN 2015-12, Unaccounted for Error Terms Associated with the Irradiation Testing and Environmental Qualification of Important-to-Safety Components 5/4/2016 AR 02614751 OE: NRC IN 2015-12 On Steris Unaccounted Dose Error Terms 06/08/2017 AR 00954985 Environmental Qualification (EQ) FASA-PM Frequency Deficiency 11/10/2009 AR 04845475 NRC ID: EPRI NP-1558 Activation Energy References (EQ) 03/14/2025 CC-AA-203 Constellation Proprietary. Environmental Qualification Program Revision 18 ER-AA-300-150 Constellation Proprietary. Cable Conditioning Monitoring Program Revision 8 MA-AA-723-500 Constellation Proprietary. Inspection of Non EQ Cables and Connections for Managing Adverse localized Environments Revision 13 NES-EIC-30.00 Constellation Proprietary. Environmental Qualification Engineering Revision 2 TID-EQ-01 Environmental Qualification Installation, Surveillance, Maintenance, Replacement of EQ Equipment Revision 0 TID-EQ-02 Environmental Qualification: Qualified Life Assessment Revision 0 TID-EQ-03 Environmental Qualification: Similarity Analysis of EQ Equipment Revision 0 TID-EQ-04 Environmental Qualification: Evaluation of the Design Basis Event (DBE) Simulation Revision 0 TID-EQ-05 Environmental Qualification Functional Performance Evaluation Revision 0
86 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition of 10 CFR 54.21(c)(1)(iii).
During the audit, the staff made the following observations:
The staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal. The applicant explained how the data for environmental parameters were monitored and how ALEs were identified. The applicant also provided environmental qualification binders that have been revised to extend the qualified life of electrical components for the subsequent period of extended operation. For these environmental qualification binders, the staff observed that the applicant utilized analytical techniques to extend the qualification of the electrical components.
The staff requested the applicant explain how it has addressed concerns with lack of technical references for activation energies for certain materials that were initially provided in EPRI Report NP-1558, A review of Equipment Aging Theory and Technology, Revision 0. NP-1558, Revision 1, resulted in the removal of about 30% of the referenced activation energies due to lack of supporting documentation. The applicant mentioned that they were aware of the issues related to the removal of activation energies in this revision and have created a corrective action report (AR 04845475) to ensure the use of any activation energy values obtained from EPRI NP-1558, Revision 0, remain valid.
The staff also audited the description of the SLRA Environmental Qualification of Electric Equipment provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the SRP-SLR.
SLRA TLAA Section 4.7.1, Reactor Building Overhead Crane Load Cycles Summary of Information in the Application. SLRA Section 4.7.1, Reactor Building Overhead Crane Load Cycles, discusses the analysis for load cycles of the Reactor Building Overhead Crane. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(i).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation - Dresden LR Revision 0 N/A Dresden Nuclear Power Station Updated Final Safety Analysis Report (UFSAR); NRC Docket Nos. STN 50-237 (Unit 2) and 50-249 (Unit 3)
Revision 15 N/A Limerick Generating Station Updated Final Safety Analysis Report, NRC Docket Nos. STN 50-352 (Unit 1) and 50-353 (Unit 2)
Revision 22
87 MA-DR-756-600 Constellation Proprietary. Dresden Reactor Disassembly Revision 03 MA-DR-756-601 Constellation Proprietary. Reactor Reassembly Revision 03 B-242 Reactor Building Framing Sections and Details Revision D Holtec International Report No. HI-951312 Topical Safety Analysis Report for the HI-STORM 100 Cask System Revision 10 LR-AA-1708 Constellation Proprietary. Time-Limited Aging Analysis (TLAA)
Identification, Evaluation, and Disposition for Subsequent License Renewal Projects Revision 1 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i).
The staff also audited the description of the SLRA TLAA Reactor Building Overhead Crane Load Cycles provided in the UFSAR supplement. The staff verified this description is consistent with the description provided in the SRP-SLR.
SLRA TLAA Section 4.7.2, Crack Growth Calculation of a Postulated Flaw in the Heat Affect Zone of an Arc Strike in the Torus Shell Summary of Information in the Application. SLRA Section 4.7.2, Crack Growth Calculation of a Postulated Flaw in the Heat Affected Zone of an Arc Strike in the Torus Shell, discusses the analysis for stress cycles in the torus shell crack growth calculation for DNPS, Unit 3. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(i).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation - Dresden LR Revision 0 N/A Dresden Nuclear Power Station Updated Final Safety Analysis Report (UFSAR); NRC Docket Nos. STN 50-237 (Unit 2) and 50-249 (Unit 3)
Revision 15 License Renewal Project TLAA Technical Report Dresden Nuclear Power Station Units 2 and 3 / Quad Cities Power Station Units 1 and 2 License Renewal Project TLAA Technical Report Revision 0 CWE-084-218 Evaluation of Suppression Chamber (Torus) Pitting - Dresden Unit 3 Revision 0 COE047.0201 Quad Cities Unit 2 - Evaluation of Torus Arc Strike Repair Revision 1 COM-27-217 Quad Cities Nuclear Power Station Units 1 and 2 - Design Report for Suppression Chamber, Vent System, and Internal Structures Revision 0 COM-02-041-2 Dresden Nuclear Power Station Units 2 and 3 - Plant Unique Analysis Report Volume 2 - Suppression Chamber Analysis Revision 0
88 ML17187B207 Dresden Nuclear Power Station Units 2 and 3 - Dresdens Response to Request for Information concerning Verification of Adequate Wall Thickness for Mark I Torus Shells, Dresden Nuclear Power Station, Units 2 and 3 (TAC Nos M95296 and M97463) - NRC Docket Numbers 50-237 and 50-249 12/01/1997 2200483.301 Dresden Cycle and Fatigue 80-Year Projections Revision 1 FP-DRES-413P Cycle Based Fatigue Report for the Transient and Fatigue Monitoring System at Dresden Generating Station Revision 1 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i).
During the audit, the staff made the following observations:
The staff reviewed Section 4.7.2 of DR-TLAABD, Revision 0, and noted it states that CWE-084-218, Revision 0, evaluated fatigue crack growth of the flaws by using the results of COE047.0201, Revision 1, Quad Cities Unit 2, Evaluation of Torus Arc Strike Repair to bound the Dresden Unit 3 flaws; and COM-27-217, Revision 0, Quad Cities Nuclear Power Station Units 1 and 2 - Design Report for Suppression Chamber, Vent System, and Internal Structures clarifies that the load cycles used in COE047.0201 include SRV actuations, pressure cycles, and temperature cycles.
The staff noted in SLRA Section 4.7.2 that (a) it is not clear whether the projected number of 75 SRV actuations can be compared with 850 load cycles and how pressure cycles and temperature cycles would affect this evaluation; (b) it is not clear what is the basis of 220 Design Transient Occurrences in SLRA Table 4.3.1-2 and how this number is used in SLRA Section 4.7.2; and (c) the projected number of actuations specified in SLRA Sections 4.7.2 and A.4.7.2 are inconsistent.
The staff will consider issuing RAIs or use a voluntary SLRA supplement to obtain the information necessary to make its finding regarding the issues identified in the second bullet of the observations above.
The staff also audited the description of the SLRA TLAA Crack Growth Calculation of a Postulated Flaw in the Heat Affected Zone of an Arc Strike in the Torus Shell provided in the UFSAR supplement Section A.4.7.2. The staff verified that this description is consistent with the description provided in the SRP-SLR.
SLRA TLAA Section 4.7.3, Radiation Degradation of Drywell Shell Expansion Gap Polyurethane Foam Summary of Information in the Application. SLRA Section 4.7.3, Radiation Degradation of Drywell Shell Expansion Gap Polyurethane Foam, discusses the analysis for the ability of the drywell shell expansion gap polyurethane foam to resist environmental radiation for the life of the plant. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(i).
To verify that the applicant provided a basis to support its disposition of the TLAA, the staff audited the TLAA.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
89 For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date TLAABD Part2, Section 4.7 TLAA Basis Document Revision 0 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i).
The staff also audited the description of the Radiation Degradation of Drywell Shell Expansion Gap Polyurethane Foam TLAA in the UFSAR supplement. The staff verified that this description is consistent with the guidance provided in the SRP-SLR.
SLRA TLAA Section 4.7.4, Generic Letter 81-11 Crack Growth Analysis To Demonstrate Conformance To The Intent Of NUREG-0619, BWR Feedwater Nozzle And Control Rod Drive Return Line Nozzle Cracking Summary of Information in the Application. SLRA Section 4.7.4, Generic Letter 81-11 Crack Growth Analysis To Demonstrate Conformance To The Intent Of NUREG-0619, BWR Feedwater Nozzle And Control Rod Drive Return Line Nozzle Cracking, discusses the analysis of cracking in the feedwater nozzles and control rod drive return line nozzles. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(iii).
Audit Activities. The staff reviewed OE documentation contained in the SLRA and ePortal, including descriptions of disposition of indications found in core shroud welds.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Part 2, Section 4.7 TLAA Basis Document - Part 2 - TLAA Evaluation Revision 0 GE-NE-523-A71-0594-A Alternate BWR Feedwater Nozzle Inspection Requirements Revision 1 May 2000 NUREG-1796 Safety Evaluation Report Related to the License Renewal of the Dresden Nuclear Power Station October 2004 ML14142A270 BWROG - Safety Evaluation of Proposed Alternative to BWR Feedwater Nozzle Inspections (TAC M94090)
June 5, 1998 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition of 10 CFR 54.21(c)(1)(iii). However, the staff found that sufficient
90 information was not available to complete its review of the applicants basis for its TLAA disposition. In order to obtain the necessary information, the staff will consider issuing an RAI.
During the audit, the staff made the following observation:
The applicant states in the TLAA evaluation and the UFSAR that, DNPS has made a commitment to maintain the inspection of these nozzles within the ISI Program.
Commitment 5 of NUREG-1796 contained a commitment to incorporate the BWR Feedwater Nozzle inspections into the ISI Program but Table A.5 of the SLRA doesnt contain a specific commitment regarding BWR Feedwater Nozzles. The staff will consider asking an RAI to clarify if a commitment is missing from Table A.5 of the SLRA or if the statement regarding a commitment was referring generically to commitment 5 of NUREG-1796.
The staff also audited the description of the SLRA A.4.7.4, Generic Letter 81-11 Crack Growth Analysis To Demonstrate Conformance To The Intent Of NUREG-0619, BWR Feedwater Nozzle And Control Rod Drive Return Line Nozzle Cracking provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the SRP-SLR for plant-specific TLAAs.
SLRA TLAA Section 4.7.5, Unit 2 Core Spray Replacement Piping Fatigue and Leakage Assessment Summary of Information in the Application. SLRA Section 4.7.5, Unit 2 Core Spray Replacement Piping Fatigue and Leakage Assessment discusses the fatigue and leakage analyses for the RVI core spray replacement piping of DNPS Unit 2. The applicant dispositioned the fatigue and leakage TLAAs for the Unit 2 RVI core spray replacement piping in accordance with 10 CFR54.21(c)(1)(i). The applicant also explained that DNPS Unit 3 had performed a similar piping replacement in 2004. The applicant further indicated that the DNPS Unit 3 repair is not included in these TLAAs because the replacement piping was analyzed for a 60-year service life, which extends beyond 80 years of plant operation.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the fatigue and leakage TLAAs for the Unit 2 RVI core spray replacement piping. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation Dresden LR Revision 0 4/2/2024
91 Document Title Revision / Date GE Hitachi 007N7207 Dresden Unit 2 Jet Pump Riser Repair and Core Spray Line Lower Section Replacement Service Life Extension Evaluation Revision 0 June 2023 GE Hitachi GENE-0000-0086-0093 Dresden Nuclear Power Station Unit 2 Core Spray Line Lower Section Replacement Hardware Stress Analysis Revision 4 January 2010 During the audit of the TLAAs, the staff verified that the applicant has provided its basis that supports its disposition of 10 CFR 54.21(c)(1)(i) for the Unit 2 RVI core spray replacement piping. However, the staff found that sufficient information was not available to complete its review of the applicants basis for its TLAA disposition. In order to obtain the necessary information, the staff will consider issuing RAIs.
During the audit, the staff made the following observations. SLRA Section 4.7.5 does not clearly describe the transients and transient cycles used in the existing 40-year fatigue analysis for the core spray pipe flange (limiting component for fatigue) to confirm that the 40-year cycle accumulation rate reasonably represents the cycle accumulation rate anticipated for the reevaluation period (i.e., 45 years) for the replacement piping.
The staff also audited the description of the fatigue and leakage TLAAs in the UFSAR supplement. The staff found that sufficient information was not available to determine whether the description provided in the UFSAR supplement was an adequate description of the fatigue and leakage TLAAs. The staff will consider issuing an RAI in order to obtain the information necessary to verify the sufficiency of the UFSAR supplement description in relation to the fatigue and leakage TLAAs for the Unit 2 RVI core spray replacement piping.
SLRA TLAA Section 4.7.6, Unit 2 Reactor Pressure Vessel Closure Flange Flaw Summary of Information in the Application. SLRA Section 4.7.6, Unit 2 Reactor Pressure Vessel Closure Flange Flaw discusses the analysis of an existing flaw in the Unit 2 closure flange to upper shell circumferential weld (2-SC4-FLG). The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(i).
Audit Activities. The staff reviewed OE documentation contained in the SLRA and ePortal, including descriptions of disposition of indications found in core shroud welds.
The table below lists documents that were reviewed by the staff and were found to be relevant to the TLAA. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Part 2, Section 4.7 TLAA Basis Document - Part 2 - TLAA Evaluation Revision 0 SIA Calculation Package 1400733.301 Dresden U2 RPV Flaw Evaluation - Fall 2019 Revision 2 November 8, 2019
92 EC 0000629936 Dresden U2 RPV Top Head Flange Flaw Evaluation Fall 2019 -
D2R26 November 14, 2019 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance wtih 10 CFR 54.21(c)(1)(i).
During the audit, the staff made the following observation:
Applicant Action Item 14 of BWRVIP-74-A states that, Therefore, components that have indications that have been previously analytically evaluated in accordance with IWB-3600 until the end of the 40-year service period shall be re-evaluated for the 60-year service period corresponding to the LR term. This Is Renewal Applicant Action Item 14.
In response to BWRVIP-74-A (Applicant Action Item #14) the applicant states in Appendix C of the SLRA that, there are no components within the ASME Code Class 1 reactor coolant pressure boundary with indications that have been previously analytically evaluated until the end of the 60-year service period. The Unit 2 Reactor Pressure Vessel Closure Flange Flaw TLAA appears to fall within the scope of BWRVIP-74-A (AAI 14). However, the staff noted that the TLAA is provided in the SLRA, so the inconsistency appears to be administrative and does not warrant an RAI.
The staff also audited the description of the SLRA A.4.7.6, Dresden Nuclear Power Station Unit 2 Reactor Vessel Closure Flange Flaw TLAA provided in the UFSAR supplement. The staff verified that this description is consistent with the description provided in the SRP-SLR for plant-specific TLAAs.
SLRA TLAA Section 4.7.7, Isolation Condenser Weld Flaw Summary of Information in the Application. SLRA Section 4.7.7, Isolation Condenser Weld Flaw discusses the applicants Unit 3 flaw analysis performed for the isolation condenser inlet nozzle-to-vessel shell weld. The applicant dispositioned this TLAA in accordance with 10 CFR54.21(c)(1)(i).
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant provided a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and reviewed the OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-SSBD-SSL License Renewal Systems and Structures Scoping and Screening Basis Document Revision 1 07/21/2022 DR-PBD-AMP-XI.M1 Dresden Nuclear Power Station, Subsequent License Renewal Project, ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD, Program Basis Document Revision 1 06/09/2024
93 Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 - TLAA Evaluation Dresden LR Revision 0 04/02/2024 KPA-SWC-67-131 Stress Report Dresden 2 and 3 Isolation Condenser Revision 0 09/1967 During the audit of the TLAAs, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i) for the isolation condenser weld flaw TLAA.
The staff also audited the description of the TLAA for the isolation condenser weld flaw provided in the UFSAR supplement. The staff verified that this description is consistent with the acceptance criteria description provided in the SRP-SLR (Revision 2) Section 4.3.2.2.
SLRA TLAA Section 4.7.8, Protective Coatings Summary of Information in the Application. SLRA Section 4.7.8, Protective Coatings, discusses the analysis for the ability of the qualified coatings inside containment to resist environmental radiation for the life of the plant. The applicant dispositioned the TLAA in accordance with 10 CFR54.21(c)(1)(i).
To verify that the applicant provided a basis to support its disposition of the TLAA, the staff audited the TLAA.
Audit Activities. During its audit, the staff interviewed the applicants staff and reviewed documentation contained in the SLRA and provided by the applicant via the ePortal.
For the OE review, the applicant made a presentation on the process used to identify and evaluate the pertinent OE. Afterwards, the staff conducted its review of the applicants methodology and OE by reviewing documentation contained in the SLRA and ePortal.
The table below lists documents that were reviewed by the staff and were found to be relevant to the program. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date TLAABD Part2, Section 4.7 TLAA Basis Document Revision 0 During the audit of the TLAA, the staff verified that the applicant has provided its basis that supports its disposition in accordance with 10 CFR 54.21(c)(1)(i).
The staff also audited the description of the Protective Coating TLAA in the UFSAR supplement.
The staff verified that this description is consistent with the guidance provided in the SRP-SLR.
94 AMR Items Not Associated with an AMP SLRA Section 3.1.2.2.1, Cumulative Fatigue Damage Summary of Information in the Application. SLRA Section 3.1.2.2.1 and Table 3.1.2-3, in relation to AMR item 3.1.1-003, indicate that the RVI components are evaluated in SLRA Section 4.3 for fatigue TLAAs.
Audit Activities. The table below lists documents that were reviewed by the staff and were found relevant to the SLRA AMR item 3.1.1-003 and Section 3.1.2.2.1. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-TLAABD Time-Limited Aging Analysis (TLAA) Basis Document - Part 2 -
TLAA Evaluation Dresden LR Revision 0 4/2/2024 SIA 2200483.308 SI:FatiguePro4 Baseline, Cycle, Fatigue and EAF Projections as of 12/31/2022 for Dresden Unit 2 Revision 2 1/31/2024 SIA 2200483.309 SI:FatiguePro4 Baseline, Cycle, Fatigue and EAF Projections as of 6/30/2022 for Dresden Unit 3 Revision 1 1/30/2024 GE 007N7207 Dresden Unit 2 Jet Pump Riser Brace Repair and Core Spray Line Lower Sectional Replacement Service Life Extension Evaluation Revision 0 June 2023 N/A Reactor Vessel Internals Aging Management Review Report Revision 1 6/2/2024 During the audit, the staff made the following observation. SLRA Table 3.1.2-3 indicates that SLRA Item 3.1.1-003 is applied to the RVI components that are associated with GALL-SLR Item IV.B1.R-53 (e.g., control rod drive guide (CRDG) tube, CRDG tube base, core plate bolts, orificed fuel support and shroud support access hole cover). The staff will consider issuing RAIs to clarify which subsections of SLRA Section 4.3 address the fatigue TLAAs for the RVI components.
SLRA Section 3.5.2.2.2.6, Reduction of Strength and Mechanical Properties of Concrete Due to Irradiation Summary of Information in the Application. SLRA Section 3.5.2.2.2.6 describes the applicants Further Evaluation or FE of the aging effects of irradiation on concrete of the biological shield wall (BSW) around the reactor pressure vessel (RPV) and its support pedestal, and the RPV support steel assembly in accordance with SRP-SLR Section 3.5.2.2.2.6. During the audit, the staff reviewed plant documentation associated with SLRA Section 3.5.2.2.2.6.
Audit Activities. In addition to the in-office audit, an onsite audit was performed from December 10, 2024 to December 12, 2024. The table below lists documents that were
95 reviewed by the staff and were found to be relevant to the Further Evaluation 3.5.2.2.2.2.6. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title or Description Revision / Date Fluence 007N6555R0 GEH Proprietary. Additional Fluence Analysis Part 2 06/2023 007N2163R0 GEG Proprietary. Reactor Pressure Vessel (RPV) Flux Evaluation 12/2022 N/A Dresden Bioshield Steel Neutron Irradiation Damage, Onsite Audit Presentation 12/11/2024 BSW/pedestal concrete WO 00497712 Unit 3 Inspections: Two vertical Cracks in Biological Shield Wall at Exist Weld 07/27/2004 WO 00977419 Unit 3 Inspections: Reactor Vessel Support Skirt Ring Girder 04/18/2016 WO 01096743 Unit 2 Inspections: Reactor Vessel Support Skirt Ring Girder 07/13/2017 WO 01692107 WO 04710708 Unit 2 Inspections: Drywell Elevation 515-5 3/4" 11/06/2017 11/09/2021 WO 01692108 WO 04710709 Unit 2 Inspections: Drywell Elevation 537-1 1/4" 11/08/2017 11/09/2021 WO 01682109 Unit 2 Inspections: Drywell Elevation 562-0 10/31/2017 11/11/2021 WO 04710897 WO 01692110 WO 04710897 Unit 2 Inspections: Drywell Elevation 576-7 10/31/2017 11/11/2021 WO 01800665 WO 04851754 Unit 3 Inspections: Drywell Elevation 502-4 10/31/2018 11/03/2022 WO 01800666 WO 04851212 Unit 3 Inspections: Drywell Elevation 515-5 3/4 10/31/2018 11/01/2022 WO 01800667 WO 04851757 Unit 3 Inspections: Drywell Elevation 537-1 1/4 10/30/2018 11/02/2022 WO 01800669 WO 04851186 Unit 3 Inspections: Drywell Elevation 562-0 10/30/2018 11/05/2022 WO 01800677 WO 04851184 Unit 2 Inspections: Drywell Elevation 576-7 10/30/2018 11/05/2022 104R861 Reactor Vessel section, sheet 5, Dresden Nuclear Power Station Revision 6 UFSAR Table 3.11-1, Environment Zone Parameters for Normal Service Conditions Revision 5 Exelon Generation Drawing No. B-276 Reactor Drywell Framing Sections & Details Revision H Sargent & Laundry Drawing No. B-700 Reactor Support Plan, Sections & Details, Dresden Nuclear Power Station, Unit 3 Revision A
96 Sargent & Laundry Drawing No. B-701 Reactor Support Developed Elevation, Dresden Nuclear Power Station, Unit 3 Revision G Exelon Generation Drawing No. B-706 Reactor Drywell Framing Sections & Details, Sheet 1, Dresden Nuclear Power Station, Unit 3 Revision E Exelon Generation Drawing No. B-709 Reactor Drywell Framing Plans Elevation 575-02 & 589-2 1/2",
Dresden Nuclear Power Station, Unit 3 Revision D N/A Subsequent License Renewal Bioshield and RPV Supports Summary, Dresden Nuclear Power Station Onsite Audit Presentation 12/11/2024 N/A Photos of the Annulus Region, Bottom Head, Vessel Skirt, Undervessel, and Drywell Third Floor Uploaded 12/17/2024 Item #76-C1 (revised).docx Geometric figure showing the configuration of reactor cavity January 2025 RPV steel supports/BSW steel WO 04997402 Unit 2 inspections: Item B-K examination results (pdf pgs. 50 to 51) 11/2021 WO 01899866 Unit 2 inspections: VT-3 examination of RV support skirt (pdf pg.
149) 11/06/2017 WO 04997403 Unit 2 inspections: VT-3 examination of stabilizers (pdf pgs. 36 to 37) 11/11/2021 and 11/12/2021 WO 01692108 WO 01421524 Unit 2 inspections: BSW inspections (listed are for two elevations) 11/06/2017 11/22/2013 WO 05236469 Unit 3 inspections: Item B-K examination results (pdf pg. 38) 11/07/2022 WO 05236469 Unit 3 inspections: VT-3 examination of RV support skirt (pdf pg.
37) 11/07/2022 WO 05121032 Unit 3 inspections: VT-3 examination of stabilizers (pdf pgs. 73 to 74) 11/07/2022 WO 01800667-01 WO 01800669-01 Unit 3 inspections: BSW inspections (listed are for two elevations and include the steel liner) 10/30/18 10/30/18 WO 0497712-01 Repair of two vertical cracks in Unit 3 BSW in 2004 2004 BWRVIP-342 (EPRI TR 3002020999) - proprietary BWR Vessel and Internals Project: Aging Management of Reactor Vessel Supports for Extended Operations, EPRI January 2022 Exelon Generation Drawing No. B-276 Reactor Drywell Framing Sections & Details, Unit 2 Revision H Exelon Generation Drawing No. B-706 Reactor Drywell Framing Sections & Details, Sheet 1, Unit 3 Revision E Sargent & Lundy Drawing No. B-22 Containment Vessels Loading - Plan & Sections, Dresden Nuclear Power Station, Unit 2 Revision I Sargent & Lundy Drawing No. B-701 Reactor Support Developed Elevation, Dresden Nuclear Power Station, Unit 3 Revision G Item #76-S4.docx Clarification of reactor vessel material January 2025 Item #76-S6.docx Plots of average temperature data in annulus region in the drywell January 2025
97 During the audit, the staff made the following observations:
Fluence 007N6555R0 and 007N2163R0 describe the methodologies and results of the neutron fluence and gamma dose estimation for the RPV steel and concrete biological shield wall.
BSW/pedestal concrete The staff noted that the SLRA does not contain sufficient information showing the configuration of RPV, active core, BSW, RPV stabilizer, reactor vessel support skirt, ring girder, reactor concrete pedestal, and drywell concrete floor as well as associated component dimensions and elevations.
The staff noted that SLRA Section 3.5.2.2.2.6 does not make clear whether concrete fill within the BSW is non-structural or structural.
The staff noted that the SLRA lacks a Table 2 AMR item associated with managing the aging effect of reduction of strength; loss of mechanical properties for the reactor vessel pedestal concrete structure.
The staff noted that SLRA Section 3.5.2.2.2.6 and UFSAR Figure 3.9-1 describe lateral load transfer among RPV, BSW and drywell, however it does not make clear what the axial expansion, the truss system, and the drywell shear lug mechanism are.
RV steel supports/BSW steel Exelon Generation Drawing Nos. B-276 and B-706 show elevations of the top and bottom of the BSW.
Sargent & Lundy Drawing No. B-22 shows a general elevation view (including the elevation at Vessel 0) of the reactor vessel and BSW with respect to drywell outer wall.
Sargent & Lundy Drawing No. B-701 shows a rollout view of the BSW with elevations.
The applicant clarified in Item #76-S4.docx that Table 5.2-2 of the Dresden UFSAR should specify SA-302 Grade B (modified with Code Case 1339) for the reactor vessel material and that this clarification will be entered into the corrective action program system for resolution.
In Item #76-S6.docx, the applicant provided plots of summer and winter (2022 to 2024) temperature data that confirm the average temperature in the annulus region between the RV and BSW is much greater than the 91.5°F stated in SLRA Section 3.5.2.2.2.6 as the lowest permissible service temperature for the reactor shield wall steel.
The staff noted that the SLRA lacks Table 2 AMR items for managing the aging effect of loss of fracture toughness due to irradiation for steel components.
The staff will consider issuing RAIs and/or use a voluntary SLRA supplement offered by the applicant to obtain the necessary information to address issues identified and communicated
98 during the audit. The staff will document its review of this information and resolution of the issues in the SE.
During the onsite audit, the applicant provided a presentation on overview of irradiation for FE 3.5.2.2.2.6 as follows:
General arrangement of the support system for the RPV and load transfer (vertical and lateral) from the RPV to the concrete pedestal and to the BSW.
RPV support system between Dresden Units 2 and 3 is the same.
AMR items (including aging effects) for RPV steel support structure (skirts, seismic restraints and stabilizer lateral support structural components), BSW steel structural components and liners, BSW concrete, RV pedestal concrete, structural bolts, anchor bolts, ring girders, welds, sole plates and grout, and a discussion of how and what AMPs will manage their aging effects.
Degradations/OEs associated with these structures and components and current general material and structural condition of BSW, reactor pedestal, RPV support skirt, and RPV seismic restraints.
The staff discussed with the applicant the observed degradations and OE associated with the BSW, RPV pedestal, RPV support skirt, and RPV seismic restraints, as well as access to RPV support skirt for inspection.
Additionally, the applicant presented technical data on bioshield steel neutron irradiation damage, including peak neutron fluence (>1.0 MeV) results and associated bounding transition temperature analyses.
SLRA AMR 3.6.2.2.2, Reduced Insulation Resistance Due to Age Degradation of Cable Bus Arrangements Caused by Intrusion of Moisture, Dust, Industrial Pollution, Rain, Ice, Photolysis, Ohmic Heating and Loss of Strength of Support Structures and Louvers of Cable Bus Arrangements Due to General Corrosion and Exposure to Air Outdoor Summary of Information in the Application. A cable bus is a variation of a metal enclosed bus which is similar in construction to a metal enclosed bus, but instead of segregated or nonsegregated electrical buses, a cable bus comprises a fully enclosed metal enclosure that utilizes three-phase insulated power cables installed on insulated support blocks.
The applicant has stated, and the staff has confirmed that there is no cable bus in the scope of LR at DNPS.
SLRA Section 3.6.2.2.3, Loss of Material due to Wind-Induced Abrasion, Loss of Conductor Strength due to Corrosion, and Increased Resistance of Connection Due to Oxidation or Loss of Preload for Transmission Conductors, Switchyard Bus, and Connections.
Summary of Information in the Application. During the audit, the staff reviewed plant documentation associated with the AMR discussed in SLRA Section 3.6.2.2.3 and the following:
99 SLRA Table 3.6.1, Summary of Aging Management Evaluations for the Electrical Components, Item Number 3.6.1-004 - Transmission conductors composed of aluminum; steel exposed to air - outdoor SLRA Table 3.6.1, Item Number 3.6.1-005 - Transmission connectors composed of aluminum; steel exposed to air - outdoor SLRA Table 3.6.1, Item Number 3.6.1-006 - Switchyard bus and connections composed of aluminum; copper; bronze; stainless steel; galvanized steel exposed to air - outdoor SLRA Table 3.6.1, Item Number 3.6.1-007 - Transmission conductors composed of aluminum; steel exposed to air - outdoor Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found to be relevant to the AMR evaluation in SLRA Section 3.6.2.2.3. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-AMRBD-MEAE Materials, Environments, and Aging Effects Aging Management Review Basis Document Revision 1 ER-AA-700-1003 Constellation Proprietary. Use of Operating Experience for License Renewal Implementation / Aging Management Revision 6 Electrical Commodities Aging Management Review Report Revision 1 DR-SSBD-SBO 10 CFR 54.4(a)(3) Station Blackout Systems Scoping and Screening Basis Document Revision 1 Excel Spreadsheet DNPS Operating Experience Review Summary Print date: 9/17/24 The staff made the following observation during walkdowns:
During the onsite audit, the staff performed a walkdown of the SBO offsite power recovery path from the switchyard to the plant reserve auxiliary transformers. The staff did not observe any signs of adverse or abnormal age-related degradation with in-scope Switchyard Bus and Connections, Transmission Conductors, or Transmission Connectors.
SLRA Section 3.6.2.3.1, Fuse Holders Summary of Information in the Application. During the audit, the staff reviewed plant documentation associated with the following:
SLRA Table 3.6.1, Summary of Aging Management Evaluations for the Electrical Components, Item 3.6.1-016 notes that fuse holders (not part of active equipment):
metallic clamps composed of various metals used for electrical connections exposed to air - indoor uncontrolled have an aging effect/mechanism of increased electrical
100 resistance of connection due to chemical contamination, corrosion, and oxidation (in an air, indoor controlled environment, increased resistance of connection due to chemical contamination, corrosion and oxidation do not apply); however, this aging effect is not applicable to DNPS.
SLRA Table 3.6.1, Item 3.6.1-017 notes that fuse holders (not part of active equipment):
metallic clamps composed of various metals used for electrical connections exposed to air-indoor controlled or uncontrolled have an aging effect/mechanism of increased electrical resistance of connection due to fatigue from ohmic heating, thermal cycling, electrical transients; however, this aging effect is not applicable to DNPS.
SLRA Table 3.6.1, Item 3.6.1-018 notes that fuse holders (not part of active equipment):
metallic clamps composed of various metals used for electrical connections exposed to air - indoor controlled or uncontrolled have an aging effect/mechanism of increased electrical resistance of connection due to fatigue caused by frequent fuse removal/manipulation or vibration; however, this aging effect is not applicable to DNPS.
SLRA Table 3.6.1, Item 3.6.1-022 notes that fuse holders (not part of active equipment):
insulation material composed of electrical insulation material: bakelite; phenolic melamine or ceramic; molded polycarbonate, and other, exposed to air - indoor controlled or uncontrolled have an aging effect of reduced electrical insulation resistance due to thermal/ thermoxidative degradation of organics, radiolysis, and photolysis (ultraviolet sensitive materials only) of organics; radiation-induced oxidation; moisture intrusion; however, this aging effect is not applicable to DNPS.
Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
The table below lists documents that were reviewed by the staff and were found to be relevant to the AMR evaluation in SLRA 3.6.2.3.1. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date N/A Electrical Commodities Screening Report Part of: Electrical Grouping Revision 1 N/A DNPS Operating Experience Review Summary 09/17/2024 N/A Panel Exterior.jpeg (Fuse Pannels for RX. PROT. SYS. -
Scram Solenoid) 12/18/2024 N/A Panel Interior 1.jpeg (Reactor Protection Logic Group 5 Channels A and B) 12/18/2024 N/A Panel Interior 2.jpeg (Reactor Protection Logic Group 5 Channels A and B) 12/18/2024 AR 04845465 Unit 2 Scram Solenoid Fuse Panel Clean and Inspect 03/14/2025 AR 04845471 Unit 3 Scram Solenoid Fuse Panel Clean and Inspect 03/14/2025
101 During the audit, the staff made the followingobservations:
NUREG-2192 Table 3.6-1, Summary of Aging Management Programs for the Electrical Components Evaluated in Chapter VI of the GALL-SLR Report, identified aging effects/mechanisms on the insulation materials of fuse holders. SLRA Table 3.6.1 Item 3.6.1-022 and Table 3.6.2-1 plant-specific Note 6 indicated that there are no aging effects to be managed for the insulation materials of the in-scope fuse holders (not part of active equipment) at DNPS, but the evaluation in SLRA Section 3.6.2.3.1 appears not to address aging effects/mechanisms on the insulation materials of the in-scope fuse holders. In response to a staff breakout question, the applicant stated that the insulation materials for the in-scope fuse holders were not subject to the aging effects/mechanisms identified in the NUREG-2192 Table 3.6-1 because they are not subjected to elevated temperatures, high radiation levels, or moisture during normal conditions. The applicant supplemented SLRA Section 3.6.2.3.1 with information that clarified the AMR of the in-scope fuse holders insulation materials in SLRA Supplement 1 (ML25051A253).
The staff requested the applicant upload pictures of in-scope fuse holder panels and their contents to the ePortal. During its review of the pictures, the staff noted discoloration in the bottom of all the fuse holder panels. The applicant explained that the discoloration in the bottom of the fuse holder panels is the buildup of minor dust and debris and, in one case, rust. The applicant stated that the rust in the one fuse holder panel is the result of water in-leakage that occurred in 1998 that is no longer active. The applicant noted that there are no impacts of the buildup of dust and debris on the components inside the panels and no corrosion was found on the fuse holders because of the rust in the bottom of the one panel. The applicant stated that requests have been submitted to document the condition of the panels and to request a cleaning and inspection of the panels. The applicant also stated that an existing work order (WO 00416381 identified in AR 04845471) will address the condition of the one panel by removing rust and resealing it during an upcoming outage to ensure that any potential future degradation is more readily detectable. The applicants explanation and corrective actions sufficiently addressed the staffs aging management concerns for in-scope fuse holders.
SLRA Section 3.6.2.3.2, High Voltage Electrical Insulators Summary of Information in the Application. During the audit, the staff reviewed plant documentation associated with the AMR discussed in SLRA Section 3.6.2.3.2 and the following:
SLRA Table 3.6.1, Summary of Aging Management Evaluations for the Electrical Components, Item Number 3.6.1-002 - High-voltage electrical insulators composed of porcelain; malleable iron; aluminum; galvanized steel; cement, toughened glass; polymers; silicone rubber; fiber glass, aluminum alloy exposed to air - outdoor SLRA Table 3.6.1, Item Number 3.6.1-003 - High-voltage electrical insulators composed of porcelain; malleable iron; aluminum; galvanized steel; cement, toughened glass; polymers; silicone rubber; fiber glass, aluminum alloy exposed to air - outdoor Audit Activities. An onsite audit was performed December 10 to December 12, 2024.
102 The table below lists documents that were reviewed by the staff and were found to be relevant to the AMR evaluation in SLRA Section 3.6.2.3.2. The staff will document its review of this information in the SE.
Relevant Documents Reviewed Document Title Revision / Date DR-AMRBD-MEAE Materials, Environments, and Aging Effects Aging Management Review Basis Document Revision 1 ER-AA-700-1003 Constellation Proprietary. Use of Operating Experience for License Renewal Implementation / Aging Management Revision 6 Electrical Commodities Aging Management Review Report Revision 1 DR-SSBD-SBO 10 CFR 54.4(a)(3) Station Blackout Systems Scoping and Screening Basis Document Revision 1 Excel Spreadsheet DNPS Operating Experience Review Summary Print date: 9/17/24 The staff made the following observation during walkdowns:
During the onsite audit, the staff performed a walkdown of the SBO offsite power recovery path from the switchyard to the plant reserve auxiliary transformers. The staff did not observe any adverse or abnormal signs of age-related degradation with in-scope high-voltage electrical insulators.
3.
Supplements to the SLRA By letters dated February 20, 2025 (ML25051A253), March 13, 2025 (ML25072A153), and April 28, 2025 (ML25118A278), CEG voluntarily submitted Supplements 1, 2, and 3, respectively, to the SLRA resulting from discussions held during the audit.
4.
Audit Questions Provided to CEG Over the course of the audit, the NRC staff provided audit questions to CEG to facilitate the audit discussions (ML25080A136).
Subject Area Meeting Date Onsite Audit 12/9/24 - 12/12/24 Inspection of Overhead Heavy Load and Light Load Handling Systems AMP 1/7/25 DNPS Reactor Building Overhead Crane Load Cycles TLAA 1/7/25 Bolting Integrity AMP 1/7/25 Water Chemistry AMP 1/7/25 Scoping and Screening Results; Mechanical: Fire Protection System 1/7/25 BWR Vessel ID Welds AMP 1/8/25 1/31/25 Fatigue Monitoring AMP 1/10/25 Metal Fatigue TLAA 1/10/25 Selective Leaching AMP 1/10/25 1/29/25
103 Subject Area Meeting Date 2/3/25 Buried and Underground Piping and Tanks AMP 1/13/25 1/15/25 ASME Section XI Inservice Inspection AMP 1/13/25 SLRA Section 3.5.2.2 1/13/25 1/15/25 1/28/25 Internal Coatings/Linings of In-Scope Piping, Piping Components, Heat Exchangers, and Tanks AMP 1/13/25 1/29/25 ASME Section XI, Subsection IWE AMP 1/14/25 ASME Section XI, Subsection IWF AMP 1/14/25 Scoping and Screening Results; Mechanical: SLRA Section 2.3 1/14/25 Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements AMP 1/14/25 Fuse Holders AMR 1/14/25 DNPS Unit 2 Reactor Vessel Closure Flange Flaw TLAA 1/15/25 GL 81-11 Crack Growth Analysis to Demonstrate Conformance to the Intent of NUREG-0619 TLAA 1/15/25 Further Evaluations in SLRA Section 3.2-3.4 - SCC and Loss of Material (pitting, crevice) for Stainless Steel, Nickel Alloys, and Aluminum Alloys 1/15/25 Non-GALL Mechanical Components 1/15/25 Flow-Accelerated Corrosion AMP 1/16/25 1/29/25 BWR Vessel Internals AMP 1/16/25 Reactor Pressure Vessel Circumferential Weld Failure Probability Analyses TLAA 1/16/25 Identification and Evaluation of TLAA 1/16/25 Fire Protection AMP 1/17/25 Fire Water System AMP 1/17/25 Monitoring of Neutron-Absorbing Materials Other Than Boraflex AMP 1/17/25 Inspection of Internal Surfaces in Misc Piping and Ducting Components AMP 1/21/25 RG 1.127, Inspection of Water-Control Structures Associated with NPPs AMP 1/21/25 2/4/25 10 CFR Part 50, Appendix J AMP 1/21/25 DNPS Unit 2 Core Spray Replacement Piping Fatigue and Leakage Assessment TLAA 1/21/25 2/10/25 2/18/25 Inaccessible Medium-Voltage Cables AMP 1/22/25 Electrical Insulation for Inaccessible I&C Cables not subject to 10 CFR 50.49 EQ AMP 1/22/25 Inaccessible Low Voltage Cables AMP 1/22/25 Reduction of Strength and Mechanical Properties of Concrete Due to Irradiation 1/30/25 1/31/25 SLRA Sections 4.2.9, 4.2.10, 4.2.11, 4.2.13 1/30/25 External Surfaces Monitoring of Mechanical Components AMP 2/6/25 Structures Monitoring AMP 2/7/25 2/21/25
104 5.
Applicant Personnel Contacted During Audit Name Affiliation Adithya Hariharan CEG Alexander Psaros CEG Alexander Rehn CEG Alexandra Fanning CEG Azekah Griffiths CEG Bashar Jabri CEG Brandon De Graaf CEG Casey Muggleston CEG Christopher Pragman CEG Daniel Oakley CEG Evan Tentinger CEG Fabian Huerta CEG Francis McGuire CEG Iba Ello Fletcher CEG Jacob Lozano CEG James Annett CEG Jennifer Lytle CEG John Frauenheim CEG Jonathan Vargas CEG Joshua Sarrafian CEG Ketan Patel CEG Kieran Kearns CEG Kurt Lindeman CEG Matthieu Stogsdill CEG Michael Smith CEG Michele Saunders CEG Morgan Ryley CEG Nicholas Lynch CEG Peter Tamburro CEG Peter Weidinger CEG Sarah Swienton CEG Sarika Malani CEG Seth Rios CEG Sharida Ullah CEG Tyler Ziegler CEG Zachary Schwartz CEG Andrew Greenop General Electric (GE)
Charles Park GE Derek Brown GE Donald Sampson GE Jeff Hren GE Larry Beese GE Scott Bowman GE 6.
Exit Meeting An exit meeting was held with the applicant on March 19, 2025, to discuss the results of the regulatory audit. The staff is considering the issuance of RAIs and RCIs to support the completion of the staffs SLRA review.